young

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Author name code: young
ADS astronomy entries on 2022-09-14
author:"Young, Peter R." -aff:"Australia"

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Title: Additions to the Spectrum of Fe IX in the 110-200 Å Region
Authors: Ryabtsev, Alexander N.; Kononov, Edward Y.; Young, Peter R.
2022ApJ...936...60R Altcode: 2022arXiv220615354R
The spectrum of eight-times ionized iron, Fe IX, was studied in the
110-200 Å region. A low inductance vacuum spark and a 3 m grazing
incidence spectrograph were used for the excitation and recording of
the spectrum. Previous analyses of Fe IX have been greatly extended and
partly revised. The number of known lines in the 3p 53d-3p
54f and 3p 53d-3p 43d 2
transition arrays is extended to 25 and 81, respectively. Most of
the identifications of the Fe IX lines from the 3p 53d-3p
43d 2 transition array in the solar spectrum
have been confirmed and several new identifications are suggested.

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Title: Properties of EUV Imaging Spectrometer (EIS) Slot Observations
Authors: Young, Peter R.; Ugarte-Urra, Ignacio
2022SoPh..297...87Y Altcode: 2022arXiv220314161Y
The Extreme ultraviolet Imaging Spectrometer (EIS) on board the Hinode
spacecraft has been operating since 2006, returning high-resolution data
in the 170 - 212 and 246 - 292 Å wavelength regions. EIS has four slit
options, with the narrow 1” and 2” slits used
for spectroscopy and the wide 40” and 266”
slits used for monochromatic imaging. In this article several
properties of the 40” slit (or slot) are measured using
the Fe XII 195.12 Å line, which is formed at 1.5 MK. The projected
width of the slot on the detector shows a small variation along the
slit with an average value of 40.949”. The slot image is
tilted on the detector and a quadratic formula is provided to describe
the tilt. The tilt corresponds to four pixels on the detector and the
slot centroid is offset mostly to the right (longer wavelengths) of the
1” slit by up to four pixels. Measurement of the intensity
decrease at the edge of the slot leads to an estimate of the spatial
resolution of the images in the x -direction. The resolution varies
quadratically along the slot, with a minimum value of 2.9”
close to the detector center. Intensities measured from the slot
images are found to be on average 14% higher than those measured
from the 1” slit at the same spatial location. Background
subtraction is necessary to derive accurate intensities in quiet-Sun
and coronal-hole regions. Prescriptions for deriving accurate slot
intensities for different types of slot datasets are presented.

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Title: Investigating Solar Wind Formation in the Inner Corona Using
ADAPT-WSA
Authors: Wallace, Samantha; Young, Peter; Arge, Charles; Viall,
Nicholeen; Jones, Shaela
2022cosp...44.1321W Altcode:
Several fundamental outstanding questions in heliophysics pertain to
the genesis and energization of the solar wind - both of which are
driven by physical processes that largely occur in the inner solar
corona. Recent and upcoming missions enable more direct measurements
of the inner corona; however, the use of a model is required to bridge
in situ and remote observations to investigate how the solar wind was
formed. We present results from aggregate work that support this claim,
where we use the Wang-Sheeley-Arge (WSA) model driven by Air Force
Data Assimilative Photospheric Flux Transport (ADAPT) time-dependent
photospheric field maps to connect in situ solar wind observations from
various spacecraft (e.g., PSP, SolO, ACE, Helios) to their source
regions at 1 Rs. We show results in which we apply our modeling
to test solar wind formation theories (e.g., reconnection/S-web,
waves-turbulence, expansion factor), and to characterize the solar wind
from specific sources (e.g., active region vs. quiet Sun coronal hole
boundaries, deep inside coronal holes). We discuss several current and
former collaborations, including connecting PSP in situ measurements
to remote composition measurements from Hinode/EIS, and identifying
the sources of transient eruptions observed at PSP. We close with how
ADAPT-WSA is currently supporting both the PSP and SolO missions.

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Title: Scattered light in the Hinode/EIS and SDO/AIA instruments
measured from the 2012 Venus transit
Authors: Young, Peter R.; Viall, Nicholeen M.
2022arXiv220709538Y Altcode:
Observations from the 2012 transit of Venus are used to derive empirical
formulae for long and short-range scattered light at locations on
the solar disk observed by the Hinode Extreme ultraviolet Imaging
Spectrometer (EIS) and the Solar Dynamics Observatory Atmospheric
Imaging Assembly (AIA) instruments. Long-range scattered light
comes from the entire solar disk, while short-range scattered light
is considered to come from a region within 50" of the region of
interest. The formulae were derived from the Fe XII 195.12 A emission
line observed by EIS and the AIA 193 A channel. A study of the weaker Fe
XIV 274.20 A line during the transit, and a comparison of scattering
in the AIA 193 A and 304 A channels suggests the EIS scattering
formula applies to other emission lines in the EIS wavebands. Both
formulae should be valid in regions of fairly uniform emission such as
coronal holes and quiet Sun, but not faint areas close (around 100")
to bright active regions. The formula for EIS is used to estimate the
scattered light component of Fe XII 195.12 for seven on-disk coronal
holes observed between 2010 and 2018. Scattered light contributions of
56% to 100% are found, suggesting that these features are dominated
by scattered light, consistent with earlier work of Wendeln \&amp;
Landi. Emission lines from the S X and Si X ions - formed at the same
temperature as Fe XII and often used to derive the first ionization
potential (FIP) bias from EIS data - are also expected to be dominated
by scattered light in coronal holes.

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Title: Elemental composition diagnostics for Hinode/EIS
Authors: Zambrana Prado, Natalia; Buchlin, Eric; Pelouze, Gabriel;
Young, Peter
2022cosp...44.2581Z Altcode:
In order to explore the connection between the solar atmosphere and
the solar wind, it is helpful to look at the elemental abundances for
they carry evidence of the origin region of the escaping plasma. This
is due to the first ionization potential (FIP) effect which results
in an enhancement of the abundances of low FIP elements. To provide
composition maps, we developed the Linear Combination Ratio (or LCR)
method which allows for relative abundance measurements forgoing the
need of differential emission measure inversion. This method has been
thoroughly tested on synthetic spectra and on spectroscopic data. The
proof of concept for the LCR method was published in Zambrana Prado
and Buchlin [2019], in that paper we focused on measuring the FIP
bias between sulfur and a mixture of iron and silicon. In this paper
we consider the most commonly-used EIS studies and identify element
pairs that can be used as diagnostics of the FIP effect. We apply the
LCR method and obtain FIP bias measurements in sample datasets. This
demonstrates that a large portion of the EIS archive can be used
for abundance diagnostics, and the LCR method opens the possibility
of deriving abundance ratio maps semi-automatically leading to new
data products for the community. We developed the LCR method further
by designing a numerical procedure based on a statistical approach
and the Bayes theorem to compute uncertainties of these FIP bias
diagnostics. It can take into account uncertainties in the atomic
physics and in the instrument calibration. It provides the probability
distribution of the real FIP bias of the plasma given the measurement
provided by the LCR method. Hinode has been coordinating with other
resources such as ALMA, PSP, Solar Orbiter, and DKIST, just to name a
few. These new diagnostics come as an add-on to our tool-belt, opening
the possibility to see through an additional perspective over a decade
and a half of coronal spectra.

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Title: Abundance diagnostics in active regions with Solar
Orbiter/SPICE
Authors: Giunta, Alessandra; Peter, Hardi; Parenti, Susanna; Buchlin,
Eric; Thompson, William; Auchere, Frederic; Kucera, Therese; Carlsson,
Mats; Janvier, Miho; Fludra, Andrzej; Hassler, Donald M.; Grundy,
Timothy; Sidher, Sunil; Guest, Steve; Leeks, Sarah; Fredvik, Terje;
Young, Peter
2022cosp...44.2583G Altcode:
With the launch of Solar Orbiter in February 2020, we are now able to
fully explore the link between the solar activity on the Sun and the
inner heliosphere. Elemental abundance measurements provide a key tracer
to probe the source regions of the solar wind and to track it from the
solar surface and corona to the heliosphere. Abundances of elements
with low first ionisation potential (FIP) are enhanced in the corona
relative to high-FIP elements, with respect to the photosphere. This is
known as the FIP effect, which is measured as abundance bias (FIP bias)
of low and high FIP elements. This effect is vital for understanding the
flow of mass and energy through the solar atmosphere. The comparison
between in-situ and remote sensing composition data, coupled with
modelling, will allow us to trace back the source of heliospheric
plasma. Solar Orbiter has a unique combination of in-situ and remote
sensing instruments that will help to make such a comparison. In
particular, the SPICE (Spectral Imaging of the Coronal Environment)
EUV spectrometer records spectra in two wavelength bands, 70.4-79.0
nm and 97.3-104.9 nm. SPICE is designed to provide spectroheliograms
using a core set of emission lines arising from ions of both low-FIP
and high-FIP elements such as C, N, O, Ne, Mg, S and Fe. These lines
are formed over a wide range of temperatures from 20,000 K to over 1
million K, enabling the analysis of the different layers of the solar
atmosphere. SPICE spectroheliograms can be processed to produce FIP
bias maps, which can be compared to in-situ measurements of the solar
wind composition of the same elements. During the Solar Orbiter Cruise
Phase, SPICE observed several active regions. We will present some of
these observations and discuss the SPICE diagnostic potential to derive
relative abundances (e.g., Mg/Ne) and the FIP bias in those regions.

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Title: A Spectroscopic Measurement of High Velocity Spray Plasma
from an M-class Flare and Coronal Mass Ejection
Authors: Young, Peter R.
2022arXiv220409542Y Altcode:
Coronal mass ejection spray plasma associated with the M1.5-class
flare of 16 February 2011 is found to exhibit a Doppler blue-shift
of 850 km/s - the largest value yet reported from ultraviolet (UV)
or extreme ultraviolet (EUV) spectroscopy of the solar disk and
inner corona. The observation is unusual in that the emission line
(Fe XII 193.51 A) is not observed directly, but the Doppler shift
is so large that the blue-shifted component appears in a wavelength
window at 192.82 A, intended to observe lines of O V, Fe XI and Ca
XVII. The Fe XII 195.12 A emission line is used as a proxy for the
rest component of 193.51 A. The observation highlights the risks of
using narrow wavelength windows for spectrometer observations when
observing highly-dynamic solar phenomena. The consequences of large
Doppler shifts for ultraviolet solar spectrometers, including the
upcoming Multi-slit Solar Explorer (MUSE) mission, are discussed.

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Title: Revised Analysis of Fe VII
Authors: Kramida, Alexander; Ryabtsev, Alexander N.; Young, Peter R.
2022ApJS..258...37K Altcode:
New spectrograms of multiply ionized iron have been recorded and
analyzed, targeting the Fe VII spectrum. As a result, several previously
unknown spectral lines and energy levels have been identified in this
spectrum. These new data have been analyzed together with all previously
published laboratory and astrophysical data on this spectrum. The
energy levels have been interpreted using parametric calculations
with Cowan codes. Radiative transition rates calculated in this work
supplemented other previously published calculations in constructing
a complete set of recommended transition probabilities. The ionization
energy of Fe VII has been redetermined with a fivefold improvement in
accuracy. Its new value is 1,007,928(20) cm-1, corresponding
to 124.9671(25) eV.

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Title: First observations from the SPICE EUV spectrometer on Solar
Orbiter
Authors: Fludra, A.; Caldwell, M.; Giunta, A.; Grundy, T.; Guest,
S.; Leeks, S.; Sidher, S.; Auchère, F.; Carlsson, M.; Hassler, D.;
Peter, H.; Aznar Cuadrado, R.; Buchlin, É.; Caminade, S.; DeForest,
C.; Fredvik, T.; Haberreiter, M.; Harra, L.; Janvier, M.; Kucera, T.;
Müller, D.; Parenti, S.; Schmutz, W.; Schühle, U.; Solanki, S. K.;
Teriaca, L.; Thompson, W. T.; Tustain, S.; Williams, D.; Young, P. R.;
Chitta, L. P.
2021A&A...656A..38F Altcode: 2021arXiv211011252F
 Aims: We present first science observations taken during the
commissioning activities of the Spectral Imaging of the Coronal
Environment (SPICE) instrument on the ESA/NASA Solar Orbiter
mission. SPICE is a high-resolution imaging spectrometer operating at
extreme ultraviolet (EUV) wavelengths. In this paper we illustrate
the possible types of observations to give prospective users a
better understanding of the science capabilities of SPICE. 
Methods: We have reviewed the data obtained by SPICE between April
and June 2020 and selected representative results obtained with
different slits and a range of exposure times between 5 s and 180
s. Standard instrumental corrections have been applied to the raw
data. Results: The paper discusses the first observations
of the Sun on different targets and presents an example of the full
spectra from the quiet Sun, identifying over 40 spectral lines from
neutral hydrogen and ions of carbon, oxygen, nitrogen, neon, sulphur,
magnesium, and iron. These lines cover the temperature range between
20 000 K and 1 million K (10 MK in flares), providing slices of the
Sun's atmosphere in narrow temperature intervals. We provide a list
of count rates for the 23 brightest spectral lines. We show examples
of raster images of the quiet Sun in several strong transition region
lines, where we have found unusually bright, compact structures in the
quiet Sun network, with extreme intensities up to 25 times greater
than the average intensity across the image. The lifetimes of these
structures can exceed 2.5 hours. We identify them as a transition
region signature of coronal bright points and compare their areas and
intensity enhancements. We also show the first above-limb measurements
with SPICE above the polar limb in C III, O VI, and Ne VIII lines, and
far off limb measurements in the equatorial plane in Mg IX, Ne VIII,
and O VI lines. We discuss the potential to use abundance diagnostics
methods to study the variability of the elemental composition that can
be compared with in situ measurements to help confirm the magnetic
connection between the spacecraft location and the Sun's surface,
and locate the sources of the solar wind. Conclusions: The
SPICE instrument successfully performs measurements of EUV spectra
and raster images that will make vital contributions to the scientific
success of the Solar Orbiter mission.

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Title: An Analysis of Spikes in Atmospheric Imaging Assembly
(AIA) Data
Authors: Young, Peter R.; Viall, Nicholeen M.; Kirk, Michael S.;
Mason, Emily I.; Chitta, Lakshmi Pradeep
2021SoPh..296..181Y Altcode: 2021arXiv210802624Y
The Atmospheric Imaging Assembly (AIA) onboard the Solar Dynamics
Observatory (SDO) returns high-resolution images of the solar atmosphere
in seven extreme ultraviolet (EUV) wavelength channels. The images
are processed on the ground to remove intensity spikes arising from
energetic particles hitting the instrument, and the despiked images
are provided to the community. In this article, a three-hour series of
images from the 171 Å channel obtained on 28 February 2017 was studied
to investigate how often the despiking algorithm gave false positives
caused by compact brightenings in the solar atmosphere. The latter
were identified through spikes appearing in the same detector pixel
for three consecutive frames. 1096 examples were found from the 900
image frames. These "three-spikes" were assigned to 126 dynamic solar
features, and it is estimated that the three-spike method identifies
19% of the total number of features affected by despiking. For any
ten-minute sequence of AIA 171 Å images there are around 37 solar
features that have their intensity modified by despiking. The features
are found in active regions, quiet Sun, and coronal holes and, in
relation to solar surface area, there is a greater proportion within
coronal holes. In 96% of the cases, the despiked structure is a compact
brightening with a size of two arcsec or less, and the remaining 4%
have narrow, elongated structures. By applying an EUV burst detection
algorithm, we found that 96% of the events could be classified as EUV
bursts. None of the spike events are rendered invisible by the AIA
processing pipeline, but the total intensity over an event's lifetime
can be reduced by up to 67%. Users are recommended to always restore
the original intensities in AIA data when studying short-lived or
rapidly evolving features that exhibit fine-scale structure.

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Title: Characterizing the Spectral Profiles of Mg II, C II and Si
IV in Solar Flares
Authors: Roy, Soumya; Tripathi, Durgesh; Young, Peter
2021AGUFMSH25E2128R Altcode:
Solar flares are the most energetic phenomena in the solar atmosphere
with consequences for space weather through the generation of
solar energetic particles and/or CMEs. Despite tremendous advances
in understanding their characteristics, the complete physics of
their origin and response to plasma in various layers of the solar
atmosphere is not fully developed. Here, we study the characteristics
of the spectral line profiles during different stages of flares as
a function of photospheric magnetic flux density and compare those
with the characteristics observed in quiescent active regions and
quiet sun. For this purpose, we use archival observations from the
Interface Region Imaging Spectrograph (IRIS). For context purposes,
we used full-disk observations from the Atmospheric Imaging Assembly
(AIA). We use the line-of-sight (LOS) magnetograms obtained by
the Helioseismic and Magnetic Imager (HMI). We characterize the
self-absorption observed and optical depth from the line intensities
as a function of the magnetic flux density, which shows a signature
of precipitation. We also see the Mg II triplets going into emission
co-spatially in the regions where flare ribbons appear later. We use
the 2791.6 A line to localize the regions where the triplet lines are
observed. These results are important for the physics of flares and
can be useful in predicting the location of a flare kernel.

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Title: Calibrating Optical Distortions In The Solar Orbiter Spice
Spectrograph
Authors: Thompson, W.; Schühle, U.; Young, P.
2021AAS...23831302T Altcode:
The Spectral Imaging of the Coronal Environment (SPICE) instrument on
SolarOrbiter is a high-resolution imaging spectrometer operating at
extremeultraviolet (EUV) wavelengths from 70.4-79.0 nm and 97.3-104.9
nm. Asingle-mirror off-axis paraboloid focuses the solar image onto the
entranceslit of the spectrometer section. A Toroidal Variable Line Space
(TVLS)grating images the entrance slit onto a pair of MCP-intensified
APS detectors.Ray-tracing analysis prior to launch showed that the
instrument was subject toa number of small image distortions which
need to be corrected in the finaldata product. We compare the ray
tracing results with measurements made inflight. Co-alignment with
other telescopes on Solar Orbiter will also beexamined.

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Title: Future Prospects for Solar EUV and Soft X-ray Solar
Spectroscopy Missions
Authors: Young, Peter R.
2021FrASS...8...50Y Altcode: 2021arXiv210202943Y
Future prospects for solar spectroscopy missions operating in the
extreme ultraviolet (EUV) and soft X-ray (SXR) wavelength ranges,
1.2--1600~\AA, are discussed. NASA is the major funder of Solar
Physics missions, and brief summaries of the opportunities for mission
development under NASA are given. Upcoming major solar missions from
other nations are also described. The methods of observing the Sun
in the two wavelength ranges are summarized with a discussion of
spectrometer types, imaging techniques and detector options. The
major spectral features in the EUV and SXR regions are identified,
and then the upcoming instruments and concepts are summarized. The
instruments range from large spectrometers on dedicated missions,
to tiny, low-cost CubeSats launched through rideshare opportunities.

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Title: The Phosphorus-Potassium Abundance Telescope
Authors: Young, P.; Hartnett, H. E.; Hinkel, N. R.; Scowen, P.
2021BAAS...53c1234Y Altcode:
Phosphorus and potassium are essential elements for understanding
planetary habitability. Phosphorus is a key element in biological
molecules involved in metabolism and RNA and DNA, but its low
abundance in Earth's crust makes it a limiting nutrient in terrestrial
ecosystems. The radioactive isotope 40K is the dominant heat source
in planetary interiors for the first 1-2 gigayears and important
thereafter. Interior heating is necessary for degassing, building an
atmosphere, and maintaining a stable climate. Despite their importance,
there are vey few stars with measured abundances of K and P due to
difficulties in observing them from the ground. We propose a CubeSat
with a moderately high resolution (R = 25,000) near-infrared (0.9-1.6
micron) spectrograph that will obtain precision abundances for P, K,
and ancillary elements for 1000 bright, sun-like FGK main sequence
stars. This represents an order of magnitude increase in the number of
stars with P measurements and enables a robust statistical understanding
of the habitability of the solar neighborhood from the perspective of
these elements.

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Title: Heterogeneous R-Process Chromium and Titanium Ejecta from
Core Collapse Supernova Ejecta Polluted Our Solar System
Authors: Bose, M.; Schulte, J.; Vance, G.; Jansen, R. A.; Young, P.
2021LPI....52.1414B Altcode:
Star explodes / Dust everywhere / Sprinkles metal.

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Title: CHIANTI—An Atomic Database for Emission Lines. XVI. Version
10, Further Extensions
Authors: Del Zanna, G.; Dere, K. P.; Young, P. R.; Landi, E.
2021ApJ...909...38D Altcode: 2020arXiv201105211D
We present version 10 of the CHIANTI package. In this release, we
provide updated atomic models for several helium-like ions and for
all the ions of the beryllium, carbon, and magnesium isoelectronic
sequences that are abundant in astrophysical plasmas. We include rates
from large-scale atomic structure and scattering calculations that
are in many cases a significant improvement over the previous version,
especially for the Be-like sequence, which has useful line diagnostics
to measure the electron density and temperature. We have also added
new ions and updated several of them with new atomic rates and line
identifications. Also, we have added several improvements to the IDL
software, to speed up the calculations and to estimate the suppression
of dielectronic recombination.

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Title: The Coupled Role of Stellar Abundances, Exoplanet Radiogenic
Heat Budgets and the Lifetime of Temperate Climates on Rocky
Exoplanets
Authors: Unterborn, C.; Foley, B.; Desch, S.; Young, P.
2021BAAS...53c1226U Altcode:
A planet's heat budget is a combination of the retained heat of
formation, the energy released due to the gravitational segregation
of a Fe core and decay of the long-lived radionuclides U, Th and
40K. While secular cooling and the energy of core segregation
are dependent on the formation history and magma ocean evolution,
the amount of radiogenic heat a planet contains is solely a function
of a planet's total amount of these elements. As refractory elements,
U and Th are likely to exist in the same proportions relative to rock
building elements in the planet as in the host-star. 40K
is moderately volatile, and a planet's abundance is dependent on the
degree of processing during planet formation. Recent observations of
Solar twins show a range of stellar Th abundances between 60 and 250%
of the Sun's (Unterborn et al., 2015), with similar ranges expected
for U and bulk K. If this range of radionuclide compositions is
indicative of the range of exoplanet radiogenic heat budgets, the
thermal and chemical evolution of these planets may be quite different
from the Earth.Here I present the results of recent coupled climate
and convection models for 1-6 Earth mass stagnant lid planet with
probabilistically determined radiogenic heat budgets constrained by
observationally-determined abundances of U, Th and K. These models
allow us to estimate the rates of surface volcanism, CO2
degassing from the interior and surface weathering processes. These
models allow us to more realistically examine the short-, medium- and
long-term climatic effects of varying radionuclide abundance given
the different half-lives of the individual elements. An important
output of our models is the lifetime of degassing across our parameter
space. Using these degassing lifetimes, I will show that the habitable
zone planets TRAPPIST-1 e, f and g are likely too old to be actively
degassing today without additional tidal heating as an additional source
of heat or the planets undergoing plate tectonics. Additionally, I will
present a sample of observed rocky exoplanets both young and massive
enough to be likely degassing today, making them prime targets in our
search for planets with temperate climates. These results show the
importance of estimating the age of a planetary system when assessing
its likelihood to harbor Earth-like and habitable exoplanets.

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Title: Extreme-ultraviolet bursts and nanoflares in the quiet-Sun
transition region and corona
Authors: Chitta, L. P.; Peter, H.; Young, P. R.
2021A&A...647A.159C Altcode: 2021arXiv210200730C
The quiet solar corona consists of myriads of loop-like features, with
magnetic fields originating from network and internetwork regions on
the solar surface. The continuous interaction between these different
magnetic patches leads to transient brightenings or bursts that might
contribute to the heating of the solar atmosphere. The literature
on a variety of such burst phenomena in the solar atmosphere is
rich. However, it remains unclear whether such transients, which are
mostly observed in the extreme ultraviolet (EUV), play a significant
role in atmospheric heating. We revisit the open question of these
bursts as a prelude to the new high-resolution EUV imagery expected
from the recently launched Solar Orbiter. We use EUV image sequences
recorded by the Atmospheric Imaging Assembly (AIA) on board the Solar
Dynamics Observatory (SDO) to investigate statistical properties of
the bursts. We detect the bursts in the 171 Å filter images of AIA in
an automated way through a pixel-wise analysis by imposing different
intensity thresholds. By exploiting the high cadence (12 s) of the
AIA observations, we find that the distribution of lifetimes of these
events peaks at about 120 s. However, a significant number of events
also have lifetimes shorter than 60 s. The sizes of the detected bursts
are limited by the spatial resolution, which indicates that a larger
number of events might be hidden in the AIA data. We estimate that about
100 new bursts appear per second on the whole Sun. The detected bursts
have nanoflare-like energies of 1024 erg per event. Based
on this, we estimate that at least 100 times more events of a similar
nature would be required to account for the energy that is required
to heat the corona. When AIA observations are considered alone, the
EUV bursts discussed here therefore play no significant role in the
coronal heating of the quiet Sun. If the coronal heating of the quiet
Sun is mainly bursty, then the high-resolution EUV observations from
Solar Orbiter may be able to reduce the deficit in the number of EUV
bursts seen with SDO/AIA at least partly by detecting more such events.

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Title: Fe VII Emission Lines in the Wavelength Range 193-197 Å
Authors: Young, Peter R.; Ryabtsev, Alexander N.; Landi, Enrico
2021ApJ...908..104Y Altcode: 2020arXiv201208027Y
The identifications of Fe VII emission lines in the wavelength range
193-197 Å are discussed in the light of new measurements of laboratory
spectra and atomic data calculations. This region is of importance to
studies of solar spectra from the EUV Imaging Spectrometer (EIS) on
board the Hinode spacecraft, which has its peak sensitivity at these
wavelengths. Ten lines are measured, arising from seven fine structure
levels in the 3p53d3 configuration. Two lines have
not previously been reported and lead to new experimental energies for
the ${({a}^{2}D)}^{3}{F}_{\mathrm{2,3}}$ levels. Updated experimental
energies are obtained for the remaining levels. The new atomic model
is used to compute theoretical values for the two density diagnostic
ratios λ196.21/λ195.39 and λ196.21/λ196.06, and densities are
derived from EIS spectra of coronal loop footpoints.

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Title: Shock Interaction/Breakout Explorer (SIBEX)
Authors: Roming, P.; Bayless, A.; Brown, P.; Davis, M.; Echon, J.;
Fryer, C.; Galeazzi, M.; Young, P.; Sibex Team
2021AAS...23731503R Altcode:
We are performing a concept and feasibility study for a future
mission that would perform wide-field X-ray imaging and localization,
coupled with rapid far-UV follow-up, in order to probe the earliest
manifestations of transient astrophysical events. Some of these
transient sources include the shock breakout (SBO) of core-collapse
supernovae, shock interaction of Type Ia SNe with a companion,
electromagnetic counterparts to gravitational wave sources (e.g.,
kilonovae), tidal disruption events, cataclysmic variables, X-ray
transients, and flaring from exoplanet host stars. We discuss the
science objectives of the mission in the context of electromagnetic and
multi-messenger astrophysics, as well as the overall mission concept
and corresponding instrumentation.

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Title: New Online Undergraduate Degree in Astronomical and Planetary
Sciences
Authors: Knierman, K.; Groppi, C.; Ashcraft, T.; Coughlin, A.;
Bahamonde, J.; Patience, J.; Butler, N.; Young, P.; Van Engelen,
A.; Noble, A.; Monkiewicz, J.; Bowman, J.; Shkolnik, E.; Anbar, A.;
Hunsley, D.; Sackey, S.; Bodin, M.; Miquirray, S.; Ray, K.; Loder, M.
2021AAS...23732301K Altcode:
In Fall 2020, the School of Earth and Space Exploration at Arizona State
University began its 100% online undergraduate degree in Astronomical
and Planetary Sciences. This degree is one of the world's first online
astronomy Bachelor of Science degrees. Offered through ASU Online, this
innovative degree will prepare students for many careers including K-12
STEM teachers, technology and science journalism and writing, public
outreach, science communication officer, science policy, statistical
data analysis, and computer programming. The degree program includes
groundwork in mathematics and physical sciences, topical courses
focused on diverse fields within astronomy and planetary science, and
exposure to the engineering and computational tools and techniques
used to carry out research. Students who are interested in going
to graduate school in Astrophysics would need additional advanced
coursework not offered online beyond the degree including, but not
limited to in-person research experience. We have developed new online
courses and redesigned existing ones in support of this degree. By
utilizing innovative learning techniques and technologies for the
online realm, we are able to provide an interactive experience for
online students. Our existing online introductory astronomy course,
also taken by many non-majors, has been redesigned and features new
online adaptive and interactive laboratory experiences created with the
ASU Center of Education through eXploration (ETX). New project-based
courses include the topics of Science Communication and Problem Solving
and Programming using Python. Solving the problems of collaborative
group work in online upper division courses has benefited from piloting
new tools and technology in remotely taught in-person courses during
the pandemic. In the 4 months since our launch in June 2020, over
100 students have been accepted into our degree program with numbers
steadily increasing each week.

---------------------------------------------------------
Title: Relative coronal abundance diagnostics with Solar Orbiter/SPICE
Authors: Zambrana Prado, N.; Buchlin, E.; Peter, H.; Young, P. R.;
Auchere, F.; Carlsson, M.; Fludra, A.; Hassler, D.; Aznar Cuadrado,
R.; Caminade, S.; Caldwell, M.; DeForest, C.; Fredvik, T.; Harra,
L.; Janvier, M.; Kucera, T. A.; Giunta, A. S.; Grundy, T.; Müller,
D.; Parenti, S.; Schmutz, W. K.; Schühle, U.; Sidher, S.; Teriaca,
L.; Thompson, W. T.; Williams, D.
2020AGUFMSH038..09Z Altcode:
Linking solar activity on the surface and in the corona to the inner
heliosphere is one of Solar Orbiter's main goals. Its UV spectrometer
SPICE (SPectral Imaging of the Coronal Environment) will provide
relative abundance measurements which will be key in this quest
as different structures on the Sun have different abundances as a
consequence of the FIP (First Ionization Potential) effect. Solar
Orbiter's unique combination of remote sensing and in-situ instruments
coupled with observation from other missions such as Parker Solar
Probe will allow us to compare in-situ and remote sensing composition
data. With the addition of modeling, these new results will allow us
to trace back the source of heliospheric plasma. As high telemetry
will not always be available with SPICE, we have developed a method
for measuring relative abundances that is both telemetry efficient
and reliable. Unlike methods based on Differential Emission Measure
(DEM) inversion, the Linear Combination Ratio (LCR) method does not
require a large number of spectral lines. This new method is based
on linear combinations of UV spectral lines. The coefficients of
the combinations are optimized such that the ratio of two linear
combinations of radiances would yield the relative abundance of two
elements. We present some abundance diagnostics tested on different
combinations of spectral lines observable by SPICE.

---------------------------------------------------------
Title: Dynamics and thermal structure in the quiet Sun seen by SPICE
Authors: Peter, H.; Aznar Cuadrado, R.; Schühle, U.; Teriaca, L.;
Auchere, F.; Carlsson, M.; Fludra, A.; Hassler, D.; Buchlin, E.;
Caminade, S.; Caldwell, M.; DeForest, C.; Fredvik, T.; Harra, L. K.;
Janvier, M.; Kucera, T. A.; Giunta, A. S.; Grundy, T.; Müller, D.;
Parenti, S.; Schmutz, W. K.; Sidher, S.; Thompson, W. T.; Williams,
D.; Young, P. R.
2020AGUFMSH038..03P Altcode:
We will present some of the early data of the Spectral Imaging of the
Coronal Environment (SPICE) instrument on Solar Orbiter. One of the
unique features of SPICE is its capability to record a wide range of
wavelengths in the extreme UV with the possibility to record spectral
lines giving access to a continuous plasma temperature range from 10.000
K to well above 1 MK. The data taken so far were for commissioning
purposes and they can be used for a preliminary evaluation of the
science performance of the instrument. Here we will concentrate on
sample spectra covering the whole wavelength region and on the early
raster maps acquired in bright lines in the quiet Sun close to disk
center. Looking at different quiet Sun features we investigate the
thermal structure of the atmosphere and flow structures. For this
we apply fits to the spectral profiles and check the performance in
terms of Doppler shifts and line widths to retrieve the structure of
the network in terms of dynamics. While the amount of data available
so far is limited, we will have a first look on how quiet Sun plasma
responds to heating events. For this, we will compare spectral lines
forming at different temperatures recorded at strictly the same time.

---------------------------------------------------------
Title: First Results From SPICE EUV Spectrometer on Solar Orbiter
Authors: Fludra, A.; Caldwell, M.; Giunta, A. S.; Grundy, T.; Guest,
S.; Sidher, S.; Auchere, F.; Carlsson, M.; Hassler, D.; Peter, H.;
Aznar Cuadrado, R.; Buchlin, E.; Caminade, S.; DeForest, C.; Fredvik,
T.; Harra, L. K.; Janvier, M.; Kucera, T. A.; Leeks, S.; Mueller,
D.; Parenti, S.; Schmutz, W. K.; Schühle, U.; Teriaca, L.; Thompson,
W. T.; Tustain, S.; Williams, D.; Young, P. R.
2020AGUFMSH038..02F Altcode:
SPICE (Spectral Imaging of Coronal Environment) is one of the remote
sensing instruments onboard Solar Orbiter. It is an EUV imaging
spectrometer observing the Sun in two wavelength bands: 69.6-79.4 nm
and 96.6-105.1 nm. SPICE is capable of recording full spectra in these
bands with exposures as short as 1s. SPICE is the only Solar Orbiter
instrument that can measure EUV spectra from the disk and low corona
of the Sun and record all spectral lines simultaneously. SPICE uses
one of three narrow slits, 2"x11', 4”x11', 6”x11', or a wide slit
30”x14'. The primary mirror can be scanned in a direction perpendicular
to the slit, allowing raster images of up to 16' in size. We
present an overview of the first SPICE data taken on several days
during the instrument commissioning carried out by the RAL Space team
between 2020 April 21 and 2020 June 14. We also include results from
SPICE observations at the first Solar Orbiter perihelion at 0.52AU,
taken between June 16-21st. We give examples of full spectra
from the quiet Sun near disk centre and provide a list of key spectral
lines emitted in a range of temperatures between 10,000 K and over 1
million K, from neutral hydrogen and ions of carbon, oxygen, nitrogen,
neon, sulphur and magnesium. We show examples of first raster images
in several strong lines, obtained with different slits and a range
of exposure times between 5s and 180s. We describe the temperature
coverage and density diagnostics, determination of plasma flows, and
discuss possible applications to studies of the elemental abundances
in the corona. We also show the first off-limb measurements with SPICE,
as obtained when the spacecraft pointed at the limb.

---------------------------------------------------------
Title: Calibrating optical distortions in the Solar Orbiter SPICE
spectrograph
Authors: Thompson, W. T.; Schühle, U.; Young, P. R.; Auchere, F.;
Carlsson, M.; Fludra, A.; Hassler, D.; Peter, H.; Aznar Cuadrado, R.;
Buchlin, E.; Caldwell, M.; DeForest, C.; Fredvik, T.; Harra, L. K.;
Janvier, M.; Kucera, T. A.; Giunta, A. S.; Grundy, T.; Müller, D.;
Parenti, S.; Caminade, S.; Schmutz, W. K.; Teriaca, L.; Williams,
D.; Sidher, S.
2020AGUFMSH0360029T Altcode:
The Spectral Imaging of the Coronal Environment (SPICE) instrument on
Solar Orbiter is a high-resolution imaging spectrometer operating
at extreme ultraviolet (EUV) wavelengths from 70.4-79.0 nm and
97.3-104.9 nm. A single-mirror off-axis paraboloid focuses the solar
image onto the entrance slit of the spectrometer section. A Toroidal
Variable Line Space (TVLS) grating images the entrance slit onto a
pair of MCP-intensified APS detectors. Ray-tracing analysis prior
to launch showed that the instrument was subject to a number of
small image distortions which need to be corrected in the final data
product. We compare the ray tracing results with measurements made in
flight. Co-alignment with other telescopes on Solar Orbiter will also
be examined.

---------------------------------------------------------
Title: First results from the EUI and SPICE observations of Alpha
Leo near Solar Orbiter first perihelion
Authors: Buchlin, E.; Teriaca, L.; Giunta, A. S.; Grundy, T.; Andretta,
V.; Auchere, F.; Peter, H.; Berghmans, D.; Carlsson, M.; Fludra, A.;
Harra, L.; Hassler, D.; Long, D.; Rochus, P. L.; Schühle, U.; Aznar
Cuadrado, R.; Caldwell, M.; Caminade, S.; DeForest, C.; Fredvik, T.;
Gissot, S.; Heerlein, K.; Janvier, M.; Kraaikamp, E.; Kucera, T. A.;
Müller, D.; Parenti, S.; Schmutz, W. K.; Sidher, S.; Smith, P.;
Stegen, K.; Thompson, W. T.; Verbeeck, C.; Williams, D.; Young, P. R.
2020AGUFMSH0360024B Altcode:
On June 16th 2020 Solar Orbiter made a dedicated observing campaign
where the spacecraft pointed to the solar limb to allow some of the
high resolution instruments to observe the ingress (at the east limb)
and later the egress (west limb) of the occultation of the star Alpha
Leonis by the solar disk. The star was chosen because its luminosity and
early spectral type ensure high and stable flux at wavelengths between
100 and 122 nanometers, a range observed by the High Resolution EUI
Lyman alpha telescope (HRI-LYA) and by the long wavelength channel
of the SPICE spectrograph. Star observations, when feasible, allow
to gather a great deal of information on the instrument performances,
such as the radiometric performance and the instrument optical point
spread function (PSF). We report here the first results from the
above campaign for the two instruments.

---------------------------------------------------------
Title: Spectroscopic Constraints on the Dimension of Active Region
Loops Along the Line of Sight
Authors: Kucera, T. A.; Young, P. R.; Klimchuk, J. A.; DeForest, C.
2020AGUFMSH041..05K Altcode:
Understanding the cross sections of coronal loops and how they vary
along the loop is important both for understanding coronal heating
and how the loops are shaped by the coronal magnetic field. To better
address this question we have developed a new method to constrain the
dimension of loops along the line of sight by utilizing spectroscopic
observations. We apply this method to a cool (5.5&lt;logT&lt;6.2)
loop using data from the Hinode/EUV Imaging Spectrometer (EIS) with
supporting data from Solar Dynamic Observatory (SDO) and the Solar
TErrestrial RElations Observatory (STEREO), and discuss the results and
their limitations. Our results are consistent with circular loop cross
sections, but could also be consistent with aspect ratios of 2 or 3.

---------------------------------------------------------
Title: First results from combined EUI and SPICE observations of
Lyman lines of Hydrogen and He II
Authors: Teriaca, L.; Aznar Cuadrado, R.; Giunta, A. S.; Grundy, T.;
Parenti, S.; Auchere, F.; Vial, J. C.; Fludra, A.; Berghmans, D.;
Carlsson, M.; Harra, L.; Hassler, D.; Long, D.; Peter, H.; Rochus,
P. L.; Schühle, U.; Buchlin, E.; Caldwell, M.; Caminade, S.; DeForest,
C.; Fredvik, T.; Gissot, S.; Heerlein, K.; Janvier, M.; Kraaikamp,
E.; Kucera, T. A.; Mueller, D.; Schmutz, W. K.; Sidher, S.; Smith, P.;
Stegen, K.; Thompson, W. T.; Verbeeck, C.; Williams, D.; Young, P. R.
2020AGUFMSH0360003T Altcode:
The Solar Orbiter spacecraft carries a powerful set of remote
sensing instruments that allow studying the solar atmosphere with
unprecedented diagnostic capabilities. Many such diagnostics require
the simultaneous usage of more than one instrument. One example of that
is the capability, for the first time, to obtain (near) simultaneous
spatially resolved observations of the emission from the first three
lines of the Lyman series of hydrogen and of He II Lyman alpha. In fact,
the SPectral Imaging of the Coronal Environment (SPICE) spectrometer
can observe the Lyman beta and gamma lines in its long wavelength
(SPICE-LW) channel, the High Resolution Lyman Alpha (HRI-LYA) telescope
of the Extreme Ultraviolet Imager (EUI) acquires narrow band images in
the Lyman alpha line while the Full Disk Imager (FSI) of EUI can take
images dominated by the Lyman alpha line of ionized Helium at 30.4 nm
(FSI-304). Being hydrogen and helium the main components of our star,
these very bright transitions play an important role in the energy
budget of the outer atmosphere via radiative losses and the measurement
of their profiles and radiance ratios is a fundamental constraint to
any comprehensive modelization effort of the upper solar chromosphere
and transition region. Additionally, monitoring their average ratios
can serve as a check out for the relative radiometric performance of
the two instruments throughout the mission. Although the engineering
data acquired so far are far from ideal in terms of time simultaneity
(often only within about 1 h) and line coverage (often only Lyman beta
was acquired by SPICE and not always near simultaneous images from all
three telescopes are available) the analysis we present here still
offers a great opportunity to have a first look at the potential of
this diagnostic from the two instruments. In fact, we have identified
a series of datasets obtained at disk center and at various positions
at the solar limb that allow studying the Lyman alpha to beta radiance
ratio and their relation to He II 30.4 as a function of the position
on the Sun (disk center versus limb and quiet Sun versus coronal holes).

---------------------------------------------------------
Title: The Solar Orbiter Science Activity Plan. Translating solar
and heliospheric physics questions into action
Authors: Zouganelis, I.; De Groof, A.; Walsh, A. P.; Williams, D. R.;
Müller, D.; St Cyr, O. C.; Auchère, F.; Berghmans, D.; Fludra,
A.; Horbury, T. S.; Howard, R. A.; Krucker, S.; Maksimovic, M.;
Owen, C. J.; Rodríguez-Pacheco, J.; Romoli, M.; Solanki, S. K.;
Watson, C.; Sanchez, L.; Lefort, J.; Osuna, P.; Gilbert, H. R.;
Nieves-Chinchilla, T.; Abbo, L.; Alexandrova, O.; Anastasiadis, A.;
Andretta, V.; Antonucci, E.; Appourchaux, T.; Aran, A.; Arge, C. N.;
Aulanier, G.; Baker, D.; Bale, S. D.; Battaglia, M.; Bellot Rubio,
L.; Bemporad, A.; Berthomier, M.; Bocchialini, K.; Bonnin, X.; Brun,
A. S.; Bruno, R.; Buchlin, E.; Büchner, J.; Bucik, R.; Carcaboso,
F.; Carr, R.; Carrasco-Blázquez, I.; Cecconi, B.; Cernuda Cangas, I.;
Chen, C. H. K.; Chitta, L. P.; Chust, T.; Dalmasse, K.; D'Amicis, R.;
Da Deppo, V.; De Marco, R.; Dolei, S.; Dolla, L.; Dudok de Wit, T.;
van Driel-Gesztelyi, L.; Eastwood, J. P.; Espinosa Lara, F.; Etesi,
L.; Fedorov, A.; Félix-Redondo, F.; Fineschi, S.; Fleck, B.; Fontaine,
D.; Fox, N. J.; Gandorfer, A.; Génot, V.; Georgoulis, M. K.; Gissot,
S.; Giunta, A.; Gizon, L.; Gómez-Herrero, R.; Gontikakis, C.; Graham,
G.; Green, L.; Grundy, T.; Haberreiter, M.; Harra, L. K.; Hassler,
D. M.; Hirzberger, J.; Ho, G. C.; Hurford, G.; Innes, D.; Issautier,
K.; James, A. W.; Janitzek, N.; Janvier, M.; Jeffrey, N.; Jenkins,
J.; Khotyaintsev, Y.; Klein, K. -L.; Kontar, E. P.; Kontogiannis,
I.; Krafft, C.; Krasnoselskikh, V.; Kretzschmar, M.; Labrosse, N.;
Lagg, A.; Landini, F.; Lavraud, B.; Leon, I.; Lepri, S. T.; Lewis,
G. R.; Liewer, P.; Linker, J.; Livi, S.; Long, D. M.; Louarn, P.;
Malandraki, O.; Maloney, S.; Martinez-Pillet, V.; Martinovic, M.;
Masson, A.; Matthews, S.; Matteini, L.; Meyer-Vernet, N.; Moraitis,
K.; Morton, R. J.; Musset, S.; Nicolaou, G.; Nindos, A.; O'Brien,
H.; Orozco Suarez, D.; Owens, M.; Pancrazzi, M.; Papaioannou, A.;
Parenti, S.; Pariat, E.; Patsourakos, S.; Perrone, D.; Peter, H.;
Pinto, R. F.; Plainaki, C.; Plettemeier, D.; Plunkett, S. P.; Raines,
J. M.; Raouafi, N.; Reid, H.; Retino, A.; Rezeau, L.; Rochus, P.;
Rodriguez, L.; Rodriguez-Garcia, L.; Roth, M.; Rouillard, A. P.;
Sahraoui, F.; Sasso, C.; Schou, J.; Schühle, U.; Sorriso-Valvo, L.;
Soucek, J.; Spadaro, D.; Stangalini, M.; Stansby, D.; Steller, M.;
Strugarek, A.; Štverák, Š.; Susino, R.; Telloni, D.; Terasa, C.;
Teriaca, L.; Toledo-Redondo, S.; del Toro Iniesta, J. C.; Tsiropoula,
G.; Tsounis, A.; Tziotziou, K.; Valentini, F.; Vaivads, A.; Vecchio,
A.; Velli, M.; Verbeeck, C.; Verdini, A.; Verscharen, D.; Vilmer, N.;
Vourlidas, A.; Wicks, R.; Wimmer-Schweingruber, R. F.; Wiegelmann,
T.; Young, P. R.; Zhukov, A. N.
2020A&A...642A...3Z Altcode: 2020arXiv200910772Z
Solar Orbiter is the first space mission observing the solar plasma
both in situ and remotely, from a close distance, in and out of the
ecliptic. The ultimate goal is to understand how the Sun produces
and controls the heliosphere, filling the Solar System and driving
the planetary environments. With six remote-sensing and four in-situ
instrument suites, the coordination and planning of the operations are
essential to address the following four top-level science questions:
(1) What drives the solar wind and where does the coronal magnetic field
originate?; (2) How do solar transients drive heliospheric variability?;
(3) How do solar eruptions produce energetic particle radiation that
fills the heliosphere?; (4) How does the solar dynamo work and drive
connections between the Sun and the heliosphere? Maximising the
mission's science return requires considering the characteristics
of each orbit, including the relative position of the spacecraft
to Earth (affecting downlink rates), trajectory events (such
as gravitational assist manoeuvres), and the phase of the solar
activity cycle. Furthermore, since each orbit's science telemetry
will be downloaded over the course of the following orbit, science
operations must be planned at mission level, rather than at the level
of individual orbits. It is important to explore the way in which those
science questions are translated into an actual plan of observations
that fits into the mission, thus ensuring that no opportunities are
missed. First, the overarching goals are broken down into specific,
answerable questions along with the required observations and the
so-called Science Activity Plan (SAP) is developed to achieve this. The
SAP groups objectives that require similar observations into Solar
Orbiter Observing Plans, resulting in a strategic, top-level view of
the optimal opportunities for science observations during the mission
lifetime. This allows for all four mission goals to be addressed. In
this paper, we introduce Solar Orbiter's SAP through a series of
examples and the strategy being followed.

---------------------------------------------------------
Title: The Solar Orbiter SPICE instrument. An extreme UV imaging
spectrometer
Authors: SPICE Consortium; Anderson, M.; Appourchaux, T.; Auchère, F.;
Aznar Cuadrado, R.; Barbay, J.; Baudin, F.; Beardsley, S.; Bocchialini,
K.; Borgo, B.; Bruzzi, D.; Buchlin, E.; Burton, G.; Büchel, V.;
Caldwell, M.; Caminade, S.; Carlsson, M.; Curdt, W.; Davenne, J.;
Davila, J.; Deforest, C. E.; Del Zanna, G.; Drummond, D.; Dubau,
J.; Dumesnil, C.; Dunn, G.; Eccleston, P.; Fludra, A.; Fredvik, T.;
Gabriel, A.; Giunta, A.; Gottwald, A.; Griffin, D.; Grundy, T.; Guest,
S.; Gyo, M.; Haberreiter, M.; Hansteen, V.; Harrison, R.; Hassler,
D. M.; Haugan, S. V. H.; Howe, C.; Janvier, M.; Klein, R.; Koller,
S.; Kucera, T. A.; Kouliche, D.; Marsch, E.; Marshall, A.; Marshall,
G.; Matthews, S. A.; McQuirk, C.; Meining, S.; Mercier, C.; Morris,
N.; Morse, T.; Munro, G.; Parenti, S.; Pastor-Santos, C.; Peter, H.;
Pfiffner, D.; Phelan, P.; Philippon, A.; Richards, A.; Rogers, K.;
Sawyer, C.; Schlatter, P.; Schmutz, W.; Schühle, U.; Shaughnessy,
B.; Sidher, S.; Solanki, S. K.; Speight, R.; Spescha, M.; Szwec, N.;
Tamiatto, C.; Teriaca, L.; Thompson, W.; Tosh, I.; Tustain, S.; Vial,
J. -C.; Walls, B.; Waltham, N.; Wimmer-Schweingruber, R.; Woodward,
S.; Young, P.; de Groof, A.; Pacros, A.; Williams, D.; Müller, D.
2020A&A...642A..14S Altcode: 2019arXiv190901183A; 2019arXiv190901183S
 Aims: The Spectral Imaging of the Coronal Environment (SPICE)
instrument is a high-resolution imaging spectrometer operating at
extreme ultraviolet wavelengths. In this paper, we present the concept,
design, and pre-launch performance of this facility instrument on the
ESA/NASA Solar Orbiter mission. Methods: The goal of this paper
is to give prospective users a better understanding of the possible
types of observations, the data acquisition, and the sources that
contribute to the instrument's signal. Results: The paper
discusses the science objectives, with a focus on the SPICE-specific
aspects, before presenting the instrument's design, including optical,
mechanical, thermal, and electronics aspects. This is followed by a
characterisation and calibration of the instrument's performance. The
paper concludes with descriptions of the operations concept and data
processing. Conclusions: The performance measurements of the
various instrument parameters meet the requirements derived from the
mission's science objectives. The SPICE instrument is ready to perform
measurements that will provide vital contributions to the scientific
success of the Solar Orbiter mission.

---------------------------------------------------------
Title: The Supernova Origins of Rare Stardust Enriched with 13C
and 15N
Authors: Schulte, J.; Bose, M.; Young, P.; Vance, G.
2020LPI....51.1268S Altcode:
New 15 solar mass 3D supernova models can successfully explain several
isotope systems of many grains with enrichments in 13C and 15N.

---------------------------------------------------------
Title: Procedure for Observing Rocky Exoplanets to Maximize the
Likelihood of Atmospheric Oxygen Biosignatures
Authors: Lisse, C. M.; Desch, S. J.; Unterborn, C. T.; Kane, S. R.;
Young, P. R.; Hartnett, H. E.; Hinkel, N. R.; Shim, S. -H.; Mamajek,
E. E.
2020LPICo2195.3064L Altcode:
We present a gated observational strategy to help prioritize exoplanet
oxygen biosignature observations, in order to obtain the clearest,
most interpretable O2 biosignature information possible.

---------------------------------------------------------
Title: Impact of small-scale emerging flux from the photosphere to
the corona: a case study from IRIS
Authors: Guglielmino, Salvo L.; Young, Peter R.; Zuccarello, Francesca;
Romano, Paolo; Murabito, Mariarita
2020IAUS..354..439G Altcode:
We report on multi-wavelength ultraviolet (UV) high-resolution
observations taken with the IRIS satellite during the emergence
phase of an emerging flux region embedded in the unipolar plage of
active region NOAA 12529. These data are complemented by measurements
taken with the spectropolarimeter aboard the Hinode satellite and by
observations from SDO.

---------------------------------------------------------
Title: The Sun: Our own backyard plasma laboratory
Authors: Young, Peter R.
2020IAUS..350..333Y Altcode:
The Sun's atmosphere increases in temperature from 6000 degrees at
the surface to over a million degrees at heights of a few thousand
kilometers. This surprising temperature increase is still an active
area of scientific study, but is generally thought to be driven by
the dynamics of the Sun's magnetic field. The combination of a 2-to-3
order of magnitude temperature range and a low plasma density makes
the solar atmosphere perhaps the best natural laboratory for the
study of ionized atoms. Atomic transitions at ultraviolet (UV) and
X-ray wavelength regions generally show no optical depth effects, and
the lines are not subject to the interstellar absorption that affects
astronomical sources. Here I highlight the importance of atomic data
to modeling UV and X-ray solar spectra, with a particular focus on the
CHIANTI atomic database. Atomic data needs and problems are discussed
and future solar mission concepts presented.

---------------------------------------------------------
Title: The biogeosciences are a critical step on the path toward
detecting life on exoplanets
Authors: Hartnett, H. E.; Hinkel, N. R.; Anbar, A. D.; Desch, S. J.;
Fisher, T.; Furukawa, H.; Glaser, D.; Okie, J. G.; Unterborn, C. T.;
Vergeli, P.; Walker, S.; Young, P.
2019AGUFM.B13C..11H Altcode:
Biogeosciences as a branch of the Earth and Life Sciences integrates
theory from geology, chemistry, biology and physics to address questions
across spatial and temporal scales including the very large and the very
long. The biogeosciences evolved from studies of the modern Earth, but
they are relevant for Earth's deep past and even for exoplanets. Thus,
we can now also consider astrophysics to lie within the context of
the biogeosciences. Exoplanets may provide the ultimate test of our
understanding of biogeochemical cycles. Planets around other stars may
be habitable, but our challenge for detecting life on these planets
will be to distinguish the BIOgeochemical rates and fluxes of a living
planet, from the strictly geochemical and physical processes of an
abiotic planet. Ecosystem stoichiometry (e.g., Sterner and Elser,
2002) is a powerful theory based on the conservation of matter and
energy that provides insight into interactions between organisms and
environments at both the individual and the ecosystem scale. However,
our knowledge of the ratios of biogeochemically relevant elements
available on exoplanets is very limited, and hinders our ability to
predict planetary-scale biogeochemical processes. Here we compare
the ratios of bioessential and rock-forming elements (e.g., C, N,
P, S, and Mg, Si, Ca, Fe) for living systems, for our Solar System,
and for nearby stars (Table 1). For example, P is critical for life on
Earth but its distribution in our solar system is quite variable. Molar
C:P ratios for a Redfield approximation of plankton (e.g., C:P = 106)
differ markedly from C:P ratios for Earth's crust (2) and for our Sun
(~2200). The very limited available P data from the Hypatia Catalog
of stellar elemental abundances reveals that nearby stars have C:P =
~800, suggesting our Sun might be comparatively P-depleted. This wide
range in C:P and in other elemental ratios result from differences in
stellar composition, planet formation and differentiation processes, and
possibly the presence of life. Future work to detect life on exoplanets
will require a coordinated effort over the next centennial, where the
biogeosciences provide a crucial theoretical framework that informs
data collection and modelling from astrophysics and planetary science.

---------------------------------------------------------
Title: Spectroscopic Constraints on the Cross-sectional Asymmetry
and Expansion of Active Region Loops
Authors: Kucera, T. A.; Young, P. R.; Klimchuk, J. A.; DeForest, C. E.
2019ApJ...885....7K Altcode:
We explore the constraints that can be placed on the dimensions of
coronal loops out of the plane of the sky by utilizing spectroscopic
observations from the Hinode/EUV Imaging Spectrometer (EIS). The
usual assumption is that loop cross sections are circular. Changes in
intensity are assumed to be the result of changing density, filling
factor, and/or point of view. In this work we instead focus on the
possibility that the loop dimensions may be changing along the line of
sight while the filling factor remains constant. We apply these ideas
to two warm (5.5≲ {log}T({{K}})&lt; 6.2) loops observed by EIS in
Active Region 11150 on 2011 February 6 with supporting observations
from Solar Dynamics Observatory's Atmospheric Imaging Assembly and
the Solar TErrestrial RElations Observatory-A's Extreme Ultraviolet
Imager. Our results are generally consistent with nonexpanding loops
but could also allow linear expansions of up to a factor of 2.5 along
a 40 Mm section of one loop and up to a factor of 3.9 in another loop,
both under the assumption that the filling factor is constant along
the loop. Expansions in the plane of the sky over the same sections of
the loops are 1.5 or less. For a filling factor of 1, the results of
the analysis are consistent with circular cross sections but also with
aspect ratios of 2 or greater. Count rate statistics are an important
part of the uncertainties, but the results are also significantly
dependent on radiometric calibration of EIS and the selection of the
loop backgrounds.

---------------------------------------------------------
Title: Achievements of Hinode in the first eleven years
Authors: Hinode Review Team; Al-Janabi, Khalid; Antolin, Patrick;
Baker, Deborah; Bellot Rubio, Luis R.; Bradley, Louisa; Brooks,
David H.; Centeno, Rebecca; Culhane, J. Leonard; Del Zanna, Giulio;
Doschek, George A.; Fletcher, Lyndsay; Hara, Hirohisa; Harra,
Louise K.; Hillier, Andrew S.; Imada, Shinsuke; Klimchuk, James A.;
Mariska, John T.; Pereira, Tiago M. D.; Reeves, Katharine K.; Sakao,
Taro; Sakurai, Takashi; Shimizu, Toshifumi; Shimojo, Masumi; Shiota,
Daikou; Solanki, Sami K.; Sterling, Alphonse C.; Su, Yingna; Suematsu,
Yoshinori; Tarbell, Theodore D.; Tiwari, Sanjiv K.; Toriumi, Shin;
Ugarte-Urra, Ignacio; Warren, Harry P.; Watanabe, Tetsuya; Young,
Peter R.
2019PASJ...71R...1H Altcode:
Hinode is Japan's third solar mission following Hinotori (1981-1982)
and Yohkoh (1991-2001): it was launched on 2006 September 22 and is in
operation currently. Hinode carries three instruments: the Solar Optical
Telescope, the X-Ray Telescope, and the EUV Imaging Spectrometer. These
instruments were built under international collaboration with the
National Aeronautics and Space Administration and the UK Science and
Technology Facilities Council, and its operation has been contributed
to by the European Space Agency and the Norwegian Space Center. After
describing the satellite operations and giving a performance evaluation
of the three instruments, reviews are presented on major scientific
discoveries by Hinode in the first eleven years (one solar cycle long)
of its operation. This review article concludes with future prospects
for solar physics research based on the achievements of Hinode.

---------------------------------------------------------
Title: Multi-component Decomposition of Astronomical Spectra by
Compressed Sensing
Authors: Cheung, Mark C. M.; De Pontieu, Bart; Martínez-Sykora,
Juan; Testa, Paola; Winebarger, Amy R.; Daw, Adrian; Hansteen, Viggo;
Antolin, Patrick; Tarbell, Theodore D.; Wuelser, Jean-Pierre; Young,
Peter; MUSE Team
2019ApJ...882...13C Altcode: 2019arXiv190203890C
The signal measured by an astronomical spectrometer may be due to
radiation from a multi-component mixture of plasmas with a range of
physical properties (e.g., temperature, Doppler velocity). Confusion
between multiple components may be exacerbated if the spectrometer
sensor is illuminated by overlapping spectra dispersed from different
slits, with each slit being exposed to radiation from a different
portion of an extended astrophysical object. We use a compressed sensing
method to robustly retrieve the different components. This method can
be adopted for a variety of spectrometer configurations, including
single-slit, multi-slit (e.g., the proposed MUlti-slit Solar Explorer
mission), and slot spectrometers (which produce overlappograms).

---------------------------------------------------------
Title: Plasmoid-mediated reconnection in solar UV bursts
Authors: Peter, H.; Huang, Y. -M.; Chitta, L. P.; Young, P. R.
2019A&A...628A...8P Altcode: 2019arXiv190704335P
Context. Ultraviolet bursts are transients in the solar atmosphere with
an increased impulsive emission in the extreme UV lasting for one to
several tens of minutes. They often show spectral profiles indicative
of a bi-directional outflow in response to magnetic reconnection. Aims: To understand UV bursts, we study how motions of magnetic
elements at the surface can drive the self-consistent formation
of a current sheet resulting in plasmoid-mediated reconnection. In
particular, we want to study the role of the height of the reconnection
in the atmosphere. Methods: We conducted numerical experiments
solving the 2D magnetohydrodynamic equations from the solar surface
to the upper atmosphere. Motivated by observations, we drove a small
magnetic patch embedded in a larger system of magnetic field of opposite
polarity. This type of configuration creates an X-type neutral point
in the initial potential field. The models are characterized by the
(average) plasma-β at the height of this X point. Results:
The driving at the surface stretches the X-point into a thin current
sheet, where plasmoids appear, accelerating the reconnection, and a
bi-directional jet forms. This is consistent with what is expected
for UV bursts or explosive events, and we provide a self-consistent
model of the formation of the reconnection region in such events. The
gravitational stratification gives a natural explanation for why
explosive events are restricted to a temperature range around a few
0.1 MK, and the presence of plasmoids in the reconnection process
provides an understanding of the observed variability during the
transient events on a timescale of minutes. Conclusions: Our
numerical experiments provide a comprehensive understanding of UV bursts
and explosive events, in particular of how the atmospheric response
changes if the reconnection happens at different plasma-β, that is,
at different heights in the atmosphere. This analysis also gives
new insight into how UV bursts might be related to the photospheric
Ellerman bombs. Movie attached to Fig. 2 is available at <A
href="https://www.aanda.org/10.1051/0004-6361/201935820/olm">https://www.aanda.org</A>

---------------------------------------------------------
Title: Constraints from Hinode/EIS on the Expansion of Active Region
Loops Along the Line of Sight
Authors: Kucera, Therese A.; Young, Peter R.; Klimchuk, James A.;
DeForest, Craig
2019AAS...23411706K Altcode:
We explore the constraints that can be placed on the dimensions of
coronal loops out of the plane of the sky by utilizing spectroscopic
observations from the Hinode/EUV Imaging Spectrometer (EIS). The
usual assumption is that loop cross sections are circular. Changes
in intensity not constant with the measured width are assumed to be
the result of changing density and/or filling factor. Here we instead
focus on the possibility that the loop dimensions may be changing along
the line of sight while the filling factor remains constant. We apply
these ideas to two cool (5.5&lt;logT&lt;6.2) loops observed by EIS with
supporting observations from Solar Dynamics Observatory's Atmospheric
Imaging Assembly (SDO/AIA) and the Solar TErrestrial RElations
Observatory-A's Extreme Ultraviolet Imager (STEREO-A/EUVI). Our
results are generally consistent with non-expanding loops, but allow
for line-of-sight expansion factors up to 3-4. The uncertainties are
sizable and are driven by count rate statistics, radiometric calibration
of EIS, and the selection of the loop backgrounds.

---------------------------------------------------------
Title: Magnetic reconnection in the low atmosphere: Ellerman bombs
and UV bursts
Authors: Young, Peter R.
2019AAS...23422606Y Altcode:
Ellerman bombs (EBs) were first discovered over a hundred years ago
and are widely interpreted as magnetic reconnection events occurring
deep in the atmosphere. UV bursts have been actively studied since
the launch of IRIS in 2013 and show many similarities to EBs, but
significantly give a strong signature in the Si IV emission lines that
indicate hotter temperatures. The interpretation is again magnetic
reconnection, but in a higher layer of the atmosphere or with a
different magnetic geometry. The expected small spatial scales
of magnetic reconnection, and the tantalizing hints from recent high
resolution ground observations suggest that EBs and UV bursts will be
an ideal demonstration of DKIST's capabilities. This talk summarizes
recent results on EBs and UV bursts and identifies key observational
capabilities of DKIST.

---------------------------------------------------------
Title: Multi-component Decomposition of Astronomical Spectra by
Compressed Sensing
Authors: Cheung, Mark; De Pontieu, Bart; Martinez-Sykora, Juan; Testa,
Paola; Winebarger, Amy R.; Daw, Adrian N.; Hansteen, Viggo; Antolin,
Patrick; Tarbell, Theodore D.; Wuelser, Jean-Pierre; Young, Peter R.
2019AAS...23411603C Altcode:
The signal measured by an astronomical spectrometer may be due to
radiation from a multi-component mixture of plasmas with a range of
physical properties (e.g. temperature, Doppler velocity). Confusion
between multiple components may be exacerbated if the spectrometer
sensor is illuminated by overlapping spectra dispersed from different
slits, with each slit being exposed to radiation from a different
portion of an extended astrophysical object. We use a compressed sensing
method to robustly retrieve the different components. This method can
be adopted for a variety of spectrometer configurations, including
single-slit, multi-slit (e.g., the proposed MUlti-slit Solar Explorer
mission; MUSE) and slot spectrometers (which produce overlappograms).

---------------------------------------------------------
Title: Using Symmetric and Asymmetric Three-Dimensional Supernova
Models to Constrain the Origins of Presolar SiC Grains
Authors: Schulte, J.; Bose, M.; Young, P.; Vance, G.
2019LPI....50.1746S Altcode:
Asymmetric 3-dimensional supernova models are a good fit to the presolar
SiC X grain isotopic compositions.

---------------------------------------------------------
Title: SI IV Resonance Line Emission during Solar Flares: Non-LTE,
Nonequilibrium, Radiation Transfer Simulations
Authors: Kerr, Graham S.; Carlsson, Mats; Allred, Joel C.; Young,
Peter R.; Daw, Adrian N.
2019ApJ...871...23K Altcode: 2018arXiv181111075K
The Interface Region Imaging Spectrograph routinely observes the Si
IV resonance lines. When analyzing quiescent observations of these
lines, it has typically been assumed that they form under optically
thin conditions. This is likely valid for the quiescent Sun, but
this assumption has also been applied to the more extreme flaring
scenario. We used 36 electron-beam-driven radiation hydrodynamic
solar flare simulations, computed using the RADYN code, to probe
the validity of this assumption. Using these simulated atmospheres,
we solved the radiation transfer equations to obtain the non-LTE,
nonequilibrium populations, line profiles, and opacities for a model
silicon atom, including charge exchange processes. This was achieved
using the “minority species” version of RADYN. The inclusion of
charge exchange resulted in a substantial fraction of Si IV at cooler
temperatures than those predicted by ionization equilibrium. All
simulations with an injected energy flux F&gt; 5× {10}10
erg cm-2 s-1 resulted in optical depth effects on
the Si IV emission, with differences in both intensity and line shape
compared to the optically thin calculation. Weaker flares (down to F ≈
5 × 109 erg cm-2 s-1) also resulted
in Si IV emission forming under optically thick conditions, depending on
the other beam parameters. When opacity was significant, the atmospheres
generally had column masses in excess of 5 × 10-6 g
cm-2 over the temperature range 40-100 kK, and the Si IV
formation temperatures were between 30 and 60 kK. We urge caution
when analyzing Si IV flare observations, or when computing synthetic
emission without performing a full radiation transfer calculation.

---------------------------------------------------------
Title: Satellite observations of reconnection between emerging and
pre-existing small-scale magnetic fields
Authors: Guglielmino, S. L.; Zuccarello, F.; Young, P. R.; Romano,
P.; Murabito, M.
2019NCimC..42...33G Altcode: 2019arXiv190101056G
We report multi-wavelength ultraviolet observations taken with the IRIS
satellite, concerning the emergence phase in the upper chromosphere
and transition region of an emerging flux region (EFR) embedded in
the unipolar plage of active region NOAA 12529. The photospheric
configuration of the EFR is analyzed in detail benefitting from
measurements taken with the spectropolarimeter aboard the Hinode
satellite, when the EFR was fully developed. In addition, these data
are complemented by full-disk, simultaneous observations of the
SDO satellite, relevant to the photosphere and the corona. In the
photosphere, magnetic flux emergence signatures are recognized in the
fuzzy granulation, with dark alignments between the emerging polarities,
cospatial with highly inclined fields. In the upper atmospheric
layers, we identify recurrent brightenings that resemble UV bursts,
with counterparts in all coronal passbands. These occur at the edges of
the EFR and in the region of the arch filament system (AFS) cospatial to
the EFR. Jet activity is also found at chromospheric and coronal levels,
near the AFS and the observed brightness enhancement sites. The analysis
of the IRIS line profiles reveals the heating of dense plasma in the
low solar atmosphere and the driving of bi-directional high-velocity
flows with speeds up to 100 km/s at the same locations. Furthermore,
we detect a correlation between the Doppler velocity and line width of
the Si IV 1394 and 1402 Å line profiles in the UV burst pixels and
their skewness. Comparing these findings with previous observations
and numerical models, we suggest evidence of several long-lasting,
small-scale magnetic reconnection episodes between the emerging bipole
and the ambient field. This process leads to the cancellation of a
pre-existing photospheric flux concentration of the plage with the
opposite polarity flux patch of the EFR. The reconnection appears to
occur higher in the atmosphere than usually observed.

---------------------------------------------------------
Title: IRIS Observations of Magnetic Interactions in the Solar
Atmosphere between Preexisting and Emerging Magnetic Fields. II. UV
Emission Properties
Authors: Guglielmino, Salvo L.; Young, Peter R.; Zuccarello, Francesca
2019ApJ...871...82G Altcode: 2018arXiv181207285G
Multiwavelength ultraviolet (UV) observations by the Interface
Region Imaging Spectrograph satellite in active region NOAA 12529
have recently pointed out the presence of long-lasting brightenings,
akin to UV bursts, and simultaneous plasma ejections occurring in
the upper chromosphere and transition region during secondary flux
emergence. These signatures have been interpreted as evidence of
small-scale, recurrent magnetic reconnection episodes between the
emerging flux region (EFR) and the preexisting plage field. Here we
characterize the UV emission of these strong, intermittent brightenings
and study the surge activity above the chromospheric arch filament
system (AFS) overlying the EFR. We analyze the surges and the cospatial
brightenings observed at different wavelengths. We find an asymmetry
in the emission between the blue and red wings of the Si IV λ1402
Å and Mg II k λ2796.3 lines, which clearly outlines the dynamics of
the structures above the AFS that form during the small-scale eruptive
phenomena. We also detect a correlation between the Doppler velocity
and skewness of the Si IV λλ1394 and 1402 line profiles in the UV
burst pixels. Finally, we show that genuine emission in the Fe XII
λ1349.4 line is cospatial to the Si IV brightenings. This definitely
reveals a pure coronal counterpart to the reconnection event.

---------------------------------------------------------
Title: Solar Ultraviolet Bursts
Authors: Young, Peter R.; Tian, Hui; Peter, Hardi; Rutten, Robert J.;
Nelson, Chris J.; Huang, Zhenghua; Schmieder, Brigitte; Vissers, Gregal
J. M.; Toriumi, Shin; Rouppe van der Voort, Luc H. M.; Madjarska, Maria
S.; Danilovic, Sanja; Berlicki, Arkadiusz; Chitta, L. P.; Cheung, Mark
C. M.; Madsen, Chad; Reardon, Kevin P.; Katsukawa, Yukio; Heinzel, Petr
2018SSRv..214..120Y Altcode: 2018arXiv180505850Y
The term "ultraviolet (UV) burst" is introduced to describe small,
intense, transient brightenings in ultraviolet images of solar active
regions. We inventorize their properties and provide a definition
based on image sequences in transition-region lines. Coronal signatures
are rare, and most bursts are associated with small-scale, canceling
opposite-polarity fields in the photosphere that occur in emerging flux
regions, moving magnetic features in sunspot moats, and sunspot light
bridges. We also compare UV bursts with similar transition-region
phenomena found previously in solar ultraviolet spectrometry and
with similar phenomena at optical wavelengths, in particular Ellerman
bombs. Akin to the latter, UV bursts are probably small-scale magnetic
reconnection events occurring in the low atmosphere, at photospheric
and/or chromospheric heights. Their intense emission in lines with
optically thin formation gives unique diagnostic opportunities
for studying the physics of magnetic reconnection in the low solar
atmosphere. This paper is a review report from an International Space
Science Institute team that met in 2016-2017.

---------------------------------------------------------
Title: Extracting Solar Physics from 151 Million EUV Images
Authors: Kirk, Michael S.; Thompson, Barbara; Attie, Raphael;
Viall-Kepko, Nicki; Young, Peter
2018csc..confE..88K Altcode:
Beginning in 2010, the Solar Dynamics Observatory's Atmospheric Imaging
Assembly (SDO AIA) revolutionized solar imaging with its high temporal
and spatial resolution and coverage. The archive of extreme ultraviolet
(EUV) images is now over 150 million and continues to grow. Automated
algorithms consistently clean these images to remove magnetospheric
particle impacts on the CCD cameras, but it has been found that compact,
intense solar brightenings are often removed as well. There are now over
3 trillion "spiked pixels" that have been removed from EUV images. We
estimate that 0.001% of those are of solar origin and removed by mistake
- an unexplored dataset of about 30 million events. We take a novel
approach and survey the entire set of AIA "spike" data to identify and
group compact brightenings across the entire SDO mission. We then use
the spike database to form statistics on compact solar brightenings
without having to process large volumes of full-disk AIA data. The
qualities of the "spikes" with a solar origin represent the most
complete archive of compact EUV bright points ever assembled.

---------------------------------------------------------
Title: Predictions of DKIST/DL-NIRSP Observations for an Off-limb
Kink-unstable Coronal Loop
Authors: Snow, B.; Botha, G. J. J.; Scullion, E.; McLaughlin, J. A.;
Young, P. R.; Jaeggli, S. A.
2018ApJ...863..172S Altcode: 2018arXiv180704972S
Synthetic intensity maps are generated from a 3D kink-unstable flux
rope simulation using several DKIST/DL-NIRSP spectral lines to make
a prediction of the observational signatures of energy transport and
release. The reconstructed large field-of-view intensity mosaics and
single tile sit-and-stare high-cadence image sequences show detailed,
fine-scale structure and exhibit signatures of wave propagation,
redistribution of heat, flows, and fine-scale bursts. These fine-scale
bursts are present in the synthetic Doppler velocity maps and can be
interpreted as evidence for small-scale magnetic reconnection at the
loop boundary. The spectral lines reveal the different thermodynamic
structures of the loop, with the hotter lines showing the loop
interior and braiding and the cooler lines showing the radial edges
of the loop. The synthetic observations of DL-NIRSP are found to
preserve the radial expansion, and hence the loop radius can be
measured accurately. The electron number density can be estimated
using the intensity ratio of the Fe XIII lines at 10747 and 10798
Å. The estimated density from this ratio is correct to within ±10%
during the later phases of the evolution; however, it is less accurate
initially when line-of-sight density inhomogeneities contribute to the
Fe XIII intensity, resulting in an overprediction of the density by
≈30%. The identified signatures are all above a conservative estimate
for instrument noise and therefore will be detectable. In summary, we
have used forward modeling to demonstrate that the coronal off-limb
mode of DKIST/DL-NIRSP will be able to detect multiple independent
signatures of a kink-unstable loop and observe small-scale transient
features including loop braiding/twisting and small-scale reconnection
events occurring at the radial edge of the loop.

---------------------------------------------------------
Title: A Study of 37 UV Bursts Observed by IRIS
Authors: Young, Peter
2018tess.conf30599Y Altcode:
Ultraviolet bursts are intense, transient, compact brightenings found
in active regions that emit strongly in the transition region Si IV
emission lines observed by IRIS. They are believed to be small-scale
magnetic reconnection events that occur low in the solar atmosphere, and
thus they provide an alternative means for investigating reconnection
compared to coronal flares and nanoflares, with the advantage that
the magnetic evolution is very clearly seen. Thirty-seven UV
bursts are identified in a four hour active region IRIS observation
from 2013 October 22, and their properties compared. In particular,
we find bursts associated with moving magnetic features, a sunspot
light bridge and emerging flux. Statistics are provided in terms of:
magnetic field strengths, Si IV line profile shape parameters, coronal
and chromospheric signatures, electron density, sizes and durations.The
events will also be placed in context with other bursts that have been
reported in the literature.

---------------------------------------------------------
Title: IRIS Observations of Magnetic Interactions in the
Solar Atmosphere between Preexisting and Emerging Magnetic
Fields. I. Overall Evolution
Authors: Guglielmino, Salvo L.; Zuccarello, Francesca; Young, Peter
R.; Murabito, Mariarita; Romano, Paolo
2018ApJ...856..127G Altcode: 2018arXiv180205657G
We report multiwavelength ultraviolet observations taken with the IRIS
satellite, concerning the emergence phase in the upper chromosphere
and transition region of an emerging flux region (EFR) embedded in the
preexisting field of active region NOAA 12529 in the Sun. IRIS data are
complemented by full-disk observations of the Solar Dynamics Observatory
satellite, relevant to the photosphere and the corona. The photospheric
configuration of the EFR is also analyzed by measurements taken with
the spectropolarimeter on board the Hinode satellite, when the EFR was
fully developed. Recurrent intense brightenings that resemble UV bursts,
with counterparts in all coronal passbands, are identified at the edges
of the EFR. Jet activity is also observed at chromospheric and coronal
levels, near the observed brightenings. The analysis of the IRIS line
profiles reveals the heating of dense plasma in the low solar atmosphere
and the driving of bidirectional high-velocity flows with speed up to
100 km s-1 at the same locations. Compared with previous
observations and numerical models, these signatures suggest evidence
of several long-lasting, small-scale magnetic reconnection episodes
between the emerging bipole and the ambient field. This process leads
to the cancellation of a preexisting photospheric flux concentration
and appears to occur higher in the atmosphere than usually found in
UV bursts, explaining the observed coronal counterparts.

---------------------------------------------------------
Title: A Si IV/O IV Electron Density Diagnostic for the Analysis of
IRIS Solar Spectra
Authors: Young, P. R.; Keenan, F. P.; Milligan, R. O.; Peter, H.
2018ApJ...857....5Y Altcode: 2018arXiv180301721Y
Solar spectra of ultraviolet bursts and flare ribbons from the Interface
Region Imaging Spectrograph (IRIS) have suggested high electron
densities of &gt; {10}12 cm-3 at transition
region temperatures of 0.1 MK, based on large intensity ratios of Si
IV λ1402.77 to O IV λ1401.16. In this work, a rare observation of
the weak O IV λ1343.51 line is reported from an X-class flare that
peaked at 21:41 UT on 2014 October 24. This line is used to develop
a theoretical prediction of the Si IV λ1402.77 to O IV λ1401.16
ratio as a function of density that is recommended to be used in the
high-density regime. The method makes use of new pressure-dependent
ionization fractions that take account of the suppression of
dielectronic recombination at high densities. It is applied to two
sequences of flare kernel observations from the October 24 flare. The
first shows densities that vary between 3× {10}12 and
3× {10}13 cm-3 over a seven-minute period,
while the second location shows stable density values of around 2×
{10}12 cm-3 over a three-minute period.

---------------------------------------------------------
Title: Element Abundance Ratios in the Quiet Sun Transition Region
Authors: Young, P. R.
2018ApJ...855...15Y Altcode: 2018arXiv180105886Y
Element abundance ratios of magnesium to neon (Mg/Ne) and neon to oxygen
(Ne/O) in the transition region of the quiet Sun have been derived by
re-assessing previously published data from the Coronal Diagnostic
Spectrometer on board the Solar and Heliospheric Observatory in the
light of new atomic data. The quiet Sun Mg/Ne ratio is important for
assessing the effect of magnetic activity on the mechanism of the
first ionization potential (FIP) effect, while the Ne/O ratio can be
used to infer the solar photospheric abundance of neon, which cannot be
measured directly. The average Mg/Ne ratio is found to be 0.52 ± 0.11,
which applies over the temperature region 0.2-0.7 MK, and is consistent
with the earlier study. The Ne/O ratio is, however, about 40% larger,
taking the value 0.24 ± 0.05 that applies to the temperature range
0.08-0.40 MK. The increase is mostly due to changes in ionization and
recombination rates that affect the equilibrium ionization balance. If
the Ne/O ratio is interpreted as reflecting the photospheric ratio,
then the photospheric neon abundance is 8.08 ± 0.09 or 8.15 ± 0.10
(on a logarithmic scale for which hydrogen is 12), according to whether
the oxygen abundances of M. Asplund et al. or E. Caffau et al. are
used. The updated photospheric neon abundance implies a Mg/Ne FIP bias
for the quiet Sun of 1.6 ± 0.6.

---------------------------------------------------------
Title: Frequently Occurring Reconnection Jets from Sunspot Light
Bridges
Authors: Tian, Hui; Yurchyshyn, Vasyl; Peter, Hardi; Solanki, Sami
K.; Young, Peter R.; Ni, Lei; Cao, Wenda; Ji, Kaifan; Zhu, Yingjie;
Zhang, Jingwen; Samanta, Tanmoy; Song, Yongliang; He, Jiansen; Wang,
Linghua; Chen, Yajie
2018ApJ...854...92T Altcode: 2018arXiv180106802T
Solid evidence of magnetic reconnection is rarely reported within
sunspots, the darkest regions with the strongest magnetic fields
and lowest temperatures in the solar atmosphere. Using the world’s
largest solar telescope, the 1.6 m Goode Solar Telescope, we detect
prevalent reconnection through frequently occurring fine-scale jets
in the Hα line wings at light bridges, the bright lanes that may
divide the dark sunspot core into multiple parts. Many jets have an
inverted Y-shape, shown by models to be typical of reconnection in a
unipolar field environment. Simultaneous spectral imaging data from
the Interface Region Imaging Spectrograph show that the reconnection
drives bidirectional flows up to 200 km s-1, and that the
weakly ionized plasma is heated by at least an order of magnitude up
to ∼80,000 K. Such highly dynamic reconnection jets and efficient
heating should be properly accounted for in future modeling efforts
of sunspots. Our observations also reveal that the surge-like activity
previously reported above light bridges in some chromospheric passbands
such as the Hα core has two components: the ever-present short surges
likely to be related to the upward leakage of magnetoacoustic waves
from the photosphere, and the occasionally occurring long and fast
surges that are obviously caused by the intermittent reconnection jets.

---------------------------------------------------------
Title: Modeling Coronal Response in Decaying Active Regions with
Magnetic Flux Transport and Steady Heating
Authors: Ugarte-Urra, Ignacio; Warren, Harry P.; Upton, Lisa A.;
Young, Peter R.
2017ApJ...846..165U Altcode: 2017arXiv170804324U
We present new measurements of the dependence of the extreme ultraviolet
(EUV) radiance on the total magnetic flux in active regions as obtained
from the Atmospheric Imaging Assembly (AIA) and the Helioseismic
and Magnetic Imager on board the Solar Dynamics Observatory. Using
observations of nine active regions tracked along different stages of
evolution, we extend the known radiance—magnetic flux power-law
relationship (I\propto {{{Φ }}}α ) to the AIA 335
Å passband, and the Fe xviii 93.93 Å spectral line in the 94 Å
passband. We find that the total unsigned magnetic flux divided by the
polarity separation ({{Φ }}/D) is a better indicator of radiance for
the Fe xviii line with a slope of α =3.22+/- 0.03. We then use these
results to test our current understanding of magnetic flux evolution
and coronal heating. We use magnetograms from the simulated decay of
these active regions produced by the Advective Flux Transport model
as boundary conditions for potential extrapolations of the magnetic
field in the corona. We then model the hydrodynamics of each individual
field line with the Enthalpy-based Thermal Evolution of Loops model with
steady heating scaled as the ratio of the average field strength and the
length (\bar{B}/L) and render the Fe xviii and 335 Å emission. We find
that steady heating is able to partially reproduce the magnitudes and
slopes of the EUV radiance—magnetic flux relationships and discuss
how impulsive heating can help reconcile the discrepancies. This
study demonstrates that combined models of magnetic flux transport,
magnetic topology, and heating can yield realistic estimates for the
decay of active region radiances with time.

---------------------------------------------------------
Title: Compact solar UV burst triggered in a magnetic field with a
fan-spine topology
Authors: Chitta, L. P.; Peter, H.; Young, P. R.; Huang, Y. -M.
2017A&A...605A..49C Altcode: 2017arXiv170608059C
Context. Solar ultraviolet (UV) bursts are small-scale features
that exhibit intermittent brightenings that are thought to be due to
magnetic reconnection. They are observed abundantly in the chromosphere
and transition region, in particular in active regions. Aims:
We investigate in detail a UV burst related to a magnetic feature that
is advected by the moat flow from a sunspot towards a pore. The moving
feature is parasitic in that its magnetic polarity is opposite to that
of the spot and the pore. This comparably simple photospheric magnetic
field distribution allows for an unambiguous interpretation of the
magnetic geometry leading to the onset of the observed UV burst. 
Methods: We used UV spectroscopic and slit-jaw observations from the
Interface Region Imaging Spectrograph (IRIS) to identify and study
chromospheric and transition region spectral signatures of said UV
burst. To investigate the magnetic topology surrounding the UV burst,
we used a two-hour-long time sequence of simultaneous line-of-sight
magnetograms from the Helioseismic and Magnetic Imager (HMI) and
performed data-driven 3D magnetic field extrapolations by means of
a magnetofrictional relaxation technique. We can connect UV burst
signatures to the overlying extreme UV (EUV) coronal loops observed
by the Atmospheric Imaging Assembly (AIA). Results: The UV
burst shows a variety of extremely broad line profiles indicating
plasma flows in excess of ±200 km s-1 at times. The whole
structure is divided into two spatially distinct zones of predominantly
up- and downflows. The magnetic field extrapolations show a persistent
fan-spine magnetic topology at the UV burst. The associated 3D magnetic
null point exists at a height of about 500 km above the photosphere
and evolves co-spatially with the observed UV burst. The EUV emission
at the footpoints of coronal loops is correlated with the evolution of
the underlying UV burst. Conclusions: The magnetic field around
the null point is sheared by photospheric motions, triggering magnetic
reconnection that ultimately powers the observed UV burst and energises
the overlying coronal loops. The location of the null point suggests
that the burst is triggered low in the solar chromosphere. Movies associated to Figs. 2 and 4 are available at <A
href="http://www.aanda.org/10.1051/0004-6361/201730830/olm">http://www.aanda.org</A>

---------------------------------------------------------
Title: Nonequilibrium Processes in the Solar Corona, Transition
Region, Flares, and Solar Wind (Invited Review)
Authors: Dudík, Jaroslav; Dzifčáková, Elena; Meyer-Vernet, Nicole;
Del Zanna, Giulio; Young, Peter R.; Giunta, Alessandra; Sylwester,
Barbara; Sylwester, Janusz; Oka, Mitsuo; Mason, Helen E.; Vocks,
Christian; Matteini, Lorenzo; Krucker, Säm; Williams, David R.;
Mackovjak, Šimon
2017SoPh..292..100D Altcode: 2017arXiv170603396D
We review the presence and signatures of the non-equilibrium processes,
both non-Maxwellian distributions and non-equilibrium ionization, in
the solar transition region, corona, solar wind, and flares. Basic
properties of the non-Maxwellian distributions are described
together with their influence on the heat flux as well as on the
rates of individual collisional processes and the resulting optically
thin synthetic spectra. Constraints on the presence of high-energy
electrons from observations are reviewed, including positive detection
of non-Maxwellian distributions in the solar corona, transition
region, flares, and wind. Occurrence of non-equilibrium ionization
is reviewed as well, especially in connection to hydrodynamic and
generalized collisional-radiative modeling. Predicted spectroscopic
signatures of non-equilibrium ionization depending on the assumed
plasma conditions are summarized. Finally, we discuss the future
remote-sensing instrumentation that can be used for the detection of
these non-equilibrium phenomena in various spectral ranges.

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Title: Constraints on Nonuniform Expansion in Coronal Loops
Authors: Kucera, Therese A.; DeForest, Craig; Klimchuk, James A.;
Young, Peter R.
2017SPD....4810608K Altcode:
We use measurements of coronal loop properties to constrain the
hypothesis that coronal loops expand differently in different
directions. A long standing problem in understanding coronal loops is
that although the magnetic field is expected to expand with altitude
and does indeed seem to do so on scales of active regions, individual
loops seem to have fairly uniform diameters along the length of the
loop. Malanushenko &amp; Schrijver (2013) have suggested that loops
may be expanding, but with a non-circular cross section. In this
scenario a loop might have a constant width in the plane of the sky,
but expand along the line of sight. Furthermore, such loops might be
easier to see from the point of view that does not show expansion. We
use Hinode/EIS and SDO/AIA data to measure loop intensities, electron
densities, temperatures and dimensions in order to determine the extent
to which loops may be expanding along the line of sight.

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Title: Modeling Active Region Evolution - at the Sun’s Surface
and into the Corona
Authors: Upton, Lisa; Ugarte-Urra, Ignacio; Warren, Harry; Young,
Peter R.
2017SPD....4840502U Altcode:
The STEREO mission provides the first opportunity to track the long-term
evolution of Active Regions over multiple rotations. The Advective Flux
Transport (AFT) model is a state of the art Surface Flux Transport
model, which simulates the observed near-surface flows to model
the transport of magnetic flux over the entire Sun. Combining STEREO
observations with AFT has allowed us to characterize the flux-luminosity
relationship for He 304 Å and to validate the far-side evolution of
individual active regions produced with AFT. Here, we present recent
results in which we extend this radiance - magnetic flux power-law
relationship to the AIA 335 Å passband, and the Fe XVIII 93.93 Å
spectral line in the 94 Å passband. We use these results to test
our current understanding of magnetic flux evolution and coronal
heating by modeling the hydrodynamics of individual field lines with
the Enthalpy-based Thermal Evolution of Loops (EBTEL) model including
steady heating scaled as the ratio of the average field strength and
the length (B/L). We find that steady heating is able to partially
reproduce the EUV radiance - magnetic flux relationships and their
observed temporal evolution. We also discuss how time-dependent
heating may be able to explain the remaining discrepancies. This
study demonstrates that combined models of magnetic flux transport,
magnetic topology and heating can yield realistic estimates for the
decay of active region radiances with time.

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Title: Observational Signatures of a Kink-unstable Coronal Flux Rope
Using Hinode/EIS
Authors: Snow, B.; Botha, G. J. J.; Régnier, S.; Morton, R. J.;
Verwichte, E.; Young, P. R.
2017ApJ...842...16S Altcode: 2017arXiv170505114S
The signatures of energy release and energy transport for a
kink-unstable coronal flux rope are investigated via forward
modeling. Synthetic intensity and Doppler maps are generated from
a 3D numerical simulation. The CHIANTI database is used to compute
intensities for three Hinode/EIS emission lines that cover the
thermal range of the loop. The intensities and Doppler velocities at
simulation-resolution are spatially degraded to the Hinode/EIS pixel
size (1″), convolved using a Gaussian point-spread function (3″),
and exposed for a characteristic time of 50 s. The synthetic images
generated for rasters (moving slit) and sit-and-stare (stationary
slit) are analyzed to find the signatures of the twisted flux and the
associated instability. We find that there are several qualities of a
kink-unstable coronal flux rope that can be detected observationally
using Hinode/EIS, namely the growth of the loop radius, the increase in
intensity toward the radial edge of the loop, and the Doppler velocity
following an internal twisted magnetic field line. However, EIS cannot
resolve the small, transient features present in the simulation,
such as sites of small-scale reconnection (e.g., nanoflares).

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Title: The Electron Density in Explosive Transition Region Events
Observed by IRIS
Authors: Doschek, G. A.; Warren, H. P.; Young, P. R.
2016ApJ...832...77D Altcode:
We discuss the intensity ratio of the O IV line at 1401.16 Å to the
Si IV line at 1402.77 Å in Interface Region Imaging Spectrograph
(IRIS) spectra. This intensity ratio is important if it can be used
to measure high electron densities that cannot be measured using line
intensity ratios of two different O IV lines from the multiplet within
the IRIS wavelength range. Our discussion is in terms of considerably
earlier observations made from the Skylab manned space station and
other spectrometers on orbiting spacecraft. The earlier data on the O
IV and Si IV ratio and other intersystem line ratios not available to
IRIS are complementary to IRIS data. In this paper, we adopt a simple
interpretation based on electron density. We adopt a set of assumptions
and calculate the electron density as a function of velocity in the Si
IV line profiles of two explosive events. At zero velocity the densities
are about 2-3 × 1011 cm-3, and near 200 km
s-1 outflow speed the densities are about 1012
cm-3. The densities increase with outflow speed up to
about 150 km s-1 after which they level off. Because of the
difference in the temperature of formation of the two lines and other
possible effects such as non-ionization equilibrium, these density
measurements do not have the precision that would be available if
there were some additional lines near the formation temperature of O IV.

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Title: Exploring Coronal Dynamics: A Next Generation Solar Physics
Mission white paper
Authors: Morton, R. J.; Scullion, E.; Bloomfield, D. S.; McLaughlin,
J. A.; Regnier, S.; McIntosh, S. W.; Tomczyk, S.; Young, P.
2016arXiv161106149M Altcode:
Determining the mechanisms responsible for the heating of the
coronal plasma and maintaining and accelerating the solar wind
are long standing goals in solar physics. There is a clear need to
constrain the energy, mass and momentum flux through the solar corona
and advance our knowledge of the physical process contributing to
these fluxes. Furthermore, the accurate forecasting of Space Weather
conditions at the near-Earth environment and, more generally, the
plasma conditions of the solar wind throughout the heliosphere, require
detailed knowledge of these fluxes in the near-Sun corona. Here we
present a short case for a space-based imaging-spectrometer coronagraph,
which will have the ability to provide synoptic information on the
coronal environment and provide strict constraints on the mass, energy,
and momentum flux through the corona. The instrument would ideally
achieve cadences of $\sim10$~s, spatial resolution of 1" and observe the
corona out to 2~$R_{\sun}$. Such an instrument will enable significant
progress in our understanding of MHD waves throughout complex plasmas,
as well as potentially providing routine data products to aid Space
Weather forecasting.

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Title: Solar Coronal Jets: Observations, Theory, and Modeling
Authors: Raouafi, N. E.; Patsourakos, S.; Pariat, E.; Young, P. R.;
Sterling, A. C.; Savcheva, A.; Shimojo, M.; Moreno-Insertis, F.;
DeVore, C. R.; Archontis, V.; Török, T.; Mason, H.; Curdt, W.;
Meyer, K.; Dalmasse, K.; Matsui, Y.
2016SSRv..201....1R Altcode: 2016arXiv160702108R; 2016SSRv..tmp...31R
Coronal jets represent important manifestations of ubiquitous solar
transients, which may be the source of significant mass and energy
input to the upper solar atmosphere and the solar wind. While
the energy involved in a jet-like event is smaller than that of
"nominal" solar flares and coronal mass ejections (CMEs), jets
share many common properties with these phenomena, in particular,
the explosive magnetically driven dynamics. Studies of jets could,
therefore, provide critical insight for understanding the larger,
more complex drivers of the solar activity. On the other side of the
size-spectrum, the study of jets could also supply important clues on
the physics of transients close or at the limit of the current spatial
resolution such as spicules. Furthermore, jet phenomena may hint to
basic process for heating the corona and accelerating the solar wind;
consequently their study gives us the opportunity to attack a broad
range of solar-heliospheric problems.

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Title: VizieR Online Data Catalog: NuGrid stellar data set I. Yields
from H to Bi (Pignatari+, 2016)
Authors: Pignatari, M.; Herwig, F.; Hirschi, R.; Bennett, M.;
Rockefeller, G.; Fryer, C.; Timmes, F. X.; Ritter, C.; Heger, A.;
Jones, S.; Battino, U.; Dotter, A.; Trappitsch, R.; Diehl, S.;
Frischknecht, U.; Hungerford, A.; Magkotsios, G.; Travaglio, C.;
Young, P.
2016yCat..22250024P Altcode:
We provide a set of stellar evolution and nucleosynthesis calculations
that applies established physics assumptions simultaneously to low-
and intermediate-mass and massive star models. Our goal is to provide
an internally consistent and comprehensive nuclear production and yield
database for applications in areas such as presolar grain studies. Our
non-rotating models assume convective boundary mixing (CBM) where it
has been adopted before. We include 8 (12) initial masses for Z=0.01
(0.02). Models are followed either until the end of the asymptotic giant
branch phase or the end of Si burning, complemented by simple analytic
core-collapse supernova (SN) models with two options for fallback and
shock velocities. The explosions show which pre-SN yields will most
strongly be effected by the explosive nucleosynthesis. We discuss
how these two explosion parameters impact the light elements and the
s and p process. For low- and intermediate-mass models, our stellar
yields from H to Bi include the effect of CBM at the He-intershell
boundaries and the stellar evolution feedback of the mixing process that
produces the 13C pocket. All post-processing nucleosynthesis
calculations use the same nuclear reaction rate network and nuclear
physics input. We provide a discussion of the nuclear production across
the entire mass range organized by element group. The entirety of our
stellar nucleosynthesis profile and time evolution output are available
electronically, and tools to explore the data on the NuGrid VOspace
hosted by the Canadian Astronomical Data Centre are introduced. (12 data files).

---------------------------------------------------------
Title: Correlation of Coronal Plasma Properties and Solar Magnetic
Field in a Decaying Active Region
Authors: Ko, Yuan-Kuen; Young, Peter R.; Muglach, Karin; Warren,
Harry P.; Ugarte-Urra, Ignacio
2016ApJ...826..126K Altcode:
We present the analysis of a decaying active region observed by
the EUV Imaging Spectrometer on Hinode during 2009 December 7-11. We
investigated the temporal evolution of its structure exhibited by plasma
at temperatures from 300,000 to 2.8 million degrees, and derived the
electron density, differential emission measure, effective electron
temperature, and elemental abundance ratios of Si/S and Fe/S (as a
measure of the First Ionization Potential (FIP) Effect). We compared
these coronal properties to the temporal evolution of the photospheric
magnetic field strength obtained from the Solar and Heliospheric
Observatory Michelson Doppler Imager magnetograms. We find that, while
these coronal properties all decreased with time during this decay
phase, the largest change was at plasma above 1.5 million degrees. The
photospheric magnetic field strength also decreased with time but
mainly for field strengths lower than about 70 Gauss. The effective
electron temperature and the FIP bias seem to reach a “basal” state
(at 1.5 × 106 K and 1.5, respectively) into the quiet Sun
when the mean photospheric magnetic field (excluding all areas &lt;10 G)
weakened to below 35 G, while the electron density continued to decrease
with the weakening field. These physical properties are all positively
correlated with each other and the correlation is the strongest in
the high-temperature plasma. Such correlation properties should be
considered in the quest for our understanding of how the corona is
heated. The variations in the elemental abundance should especially
be considered together with the electron temperature and density.

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Title: Global Sausage Oscillation of Solar Flare Loops Detected by
the Interface Region Imaging Spectrograph
Authors: Tian, Hui; Young, Peter R.; Reeves, Katharine K.; Wang,
Tongjiang; Antolin, Patrick; Chen, Bin; He, Jiansen
2016ApJ...823L..16T Altcode: 2016arXiv160501963T
An observation from the Interface Region Imaging Spectrograph
reveals coherent oscillations in the loops of an M1.6 flare on 2015
March 12. Both the intensity and Doppler shift of Fe xxi 1354.08 Å
show clear oscillations with a period of ∼25 s. Remarkably similar
oscillations were also detected in the soft X-ray flux recorded by
the Geostationary Operational Environmental Satellites (GOES). With
an estimated phase speed of ∼2420 km s-1 and a derived
electron density of at least 5.4 × 1010 cm-3,
the observed short-period oscillation is most likely the global
fast sausage mode of a hot flare loop. We find a phase shift of
∼π/2 (1/4 period) between the Doppler shift oscillation and the
intensity/GOES oscillations, which is consistent with a recent forward
modeling study of the sausage mode. The observed oscillation requires
a density contrast between the flare loop and coronal background of a
factor ≥42. The estimated phase speed of the global mode provides a
lower limit of the Alfvén speed outside the flare loop. We also find
an increase of the oscillation period, which might be caused by the
separation of the loop footpoints with time.

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Title: The CHIANTI atomic database
Authors: Young, P. R.; Dere, K. P.; Landi, E.; Del Zanna, G.; Mason,
H. E.
2016JPhB...49g4009Y Altcode: 2015arXiv151205620Y
The freely available CHIANTI atomic database was first released
in 1996 and has had a huge impact on the analysis and modeling of
emissions from astrophysical plasmas. It contains data and software
for modeling optically thin atom and positive ion emission from low
density (≲1013 cm-3) plasmas from x-ray to
infrared wavelengths. A key feature is that the data are assessed
and regularly updated, with version 8 released in 2015. Atomic data
for modeling the emissivities of 246 ions and neutrals are contained
in CHIANTI, together with data for deriving the ionization fractions
of all elements up to zinc. The different types of atomic data are
summarized here and their formats discussed. Statistics on the impact
of CHIANTI to the astrophysical community are given and examples of
the diverse range of applications are presented.

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Title: A closer look at a coronal loop rooted in a sunspot umbra
Authors: Chitta, L. P.; Peter, H.; Young, P. R.
2016A&A...587A..20C Altcode: 2015arXiv151203831C
Context. Extreme UV (EUV) and X-ray loops in the solar corona connect
regions of enhanced magnetic activity, but they are not usually rooted
in the dark umbrae of sunspots because the strong magnetic field
found there suppresses convection. This means that the Poynting flux
of magnetic energy into the upper atmosphere is not significant within
the umbra as long as there are no light bridges or umbral dots. 
Aims: Here we report a rare observation of a coronal loop rooted in the
dark umbra of a sunspot without any traces of light bridges or umbral
dots. This allows us to investigate the loop without much confusion
from background or line-of-sight integration effects. Methods:
We used the slit-jaw images and spectroscopic data from the Interface
Region Imaging Spectrograph (IRIS) and concentrate on the line profiles
of O iv and Si iv that show persistent strong redshifted components in
the loop rooted in the umbra. Using the ratios of O iv, we can estimate
the density and thus investigate the mass flux. The coronal context
and temperature diagnostics of these observations is provided through
the EUV channels of the Atmospheric Imaging Assembly (AIA). 
Results: The coronal loop, embedded within cooler downflows, hosts
supersonic downflows. The speed of more than 100 km s-1 is
on the same order of magnitude in the transition region lines of O iv
and Si iv, and is even seen at comparable speed in the chromospheric
Mg II lines. At a projected distance of within 1” of the footpoint,
we see a shock transition to smaller downflow speeds of about 15
km s-1 being consistent with mass conservation across a
stationary isothermal shock. Conclusions: We see no direct
evidence for energy input into the loop because the loop is rooted
in the dark uniform part of the umbra with no light bridges or umbral
dots near by. Thus one might conclude that we are seeing a siphon flow
driven from the footpoint at the other end of the loop. However, for a
final result data of similar quality at the other footpoint are needed,
but this is too far away to be covered by the IRIS field of view.

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Title: Temporal Evolution of Chromospheric Evaporation: Case
Studies of the M1.1 Flare on 2014 September 6 and X1.6 Flare on 2014
September 10
Authors: Tian, Hui; Young, Peter R.; Reeves, Katharine K.; Chen, Bin;
Liu, Wei; McKillop, Sean
2015ApJ...811..139T Altcode: 2015arXiv150502736T
With observations from the Interface Region Imaging Spectrograph, we
track the complete evolution of ∼11 MK evaporation flows in an M1.1
flare on 2014 September 6 and an X1.6 flare on 2014 September 10. These
hot flows, as indicated by the blueshifted Fe xxi 1354.08 Å line,
evolve smoothly with a velocity decreasing exponentially from ∼200
km s-1 to almost stationary within a few minutes. We find a
good correlation between the flow velocity and energy deposition rate
as represented by the hard X-ray flux observed with the Reuven Ramaty
High Energy Solar Spectroscopic Imager, or time derivative of the soft
X-ray flux observed with the Geostationary Operational Environmental
Satellites and the HINODE X-ray Telescope, which is in general agreement
with models of nonthermal electron heating. The maximum blueshift of
Fe xxi appears approximately at the same time as or slightly after
the impulsive enhancement of the ultraviolet continuum and the Mg ii
2798.8 Å line emission, demonstrating that the evaporation flow is
closely related to heating of the lower chromosphere. Finally, while
the hot Fe xxi 1354.08 Å line is entirely blueshifted with no obvious
rest component, cool chromospheric and transition region lines like
Si iv 1402.77 Å are often not entirely redshifted but just reveal an
obvious red wing enhancement at the ribbons, suggesting that the speed
of chromospheric condensation might be larger than previously thought.

---------------------------------------------------------
Title: CHIANTI - An atomic database for emission lines. Version 8
Authors: Del Zanna, G.; Dere, K. P.; Young, P. R.; Landi, E.; Mason,
H. E.
2015A&A...582A..56D Altcode: 2015arXiv150807631D
We present version 8 of the CHIANTI database. This version includes
a large amount of new data and ions, which represent a significant
improvement in the soft X-ray, extreme UV (EUV) and UV spectral
regions, which several space missions currently cover. New data for
neutrals and low charge states are also added. The data are assessed,
but to improve the modelling of low-temperature plasma the effective
collision strengths for most of the new datasets are not spline-fitted
as previously, but are retained as calculated. This required a change
of the format of the CHIANTI electron excitation files. The format
of the energy files has also been changed. Excitation rates between
all the levels are retained for most of the new datasets, so the data
can in principle be used to model high-density plasma. In addition,
the method for computing the differential emission measure used in
the CHIANTI software has been changed.

---------------------------------------------------------
Title: Report on the O IV and S IV lines observed by IRIS
Authors: Young, Peter R.
2015arXiv150905011Y Altcode:
The O IV intercombination lines observed by the Interface Region Imaging
Spectrograph (IRIS) between 1397 and 1407 A provide useful density
diagnostics. This document presents data that address two issues related
to these lines: (1) the contribution of S IV to the O IV 1404.8 line;
and (2) the range of sensitivity of the O IV 1399.8/1401.2 ratio.

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Title: The Fast Filament Eruption Leading to the X-flare on 2014
March 29
Authors: Kleint, Lucia; Battaglia, Marina; Reardon, Kevin; Sainz Dalda,
Alberto; Young, Peter R.; Krucker, Säm
2015ApJ...806....9K Altcode: 2015arXiv150400515K
We investigate the sequence of events leading to the solar X1 flare
SOL2014-03-29T17:48. Because of the unprecedented joint observations of
an X-flare with the ground-based Dunn Solar Telescope and the spacecraft
IRIS, Hinode, RHESSI, STEREO, and the Solar Dynamics Observatory, we can
sample many solar layers from the photosphere to the corona. A filament
eruption was observed above a region of previous flux emergence, which
possibly led to a change in magnetic field configuration, causing
the X-flare. This was concluded from the timing and location of the
hard X-ray emission, which started to increase slightly less than a
minute after the filament accelerated. The filament showed Doppler
velocities of ∼2-5 km s-1 at chromospheric temperatures
for at least one hour before the flare occurred, mostly blueshifts,
but also redshifts near its footpoints. Fifteen minutes before the
flare, its chromospheric Doppler shifts increased to ∼6-10 km
s-1 and plasma heating could be observed before it lifted
off with at least 600 km s-1 as seen in IRIS data. Compared
to previous studies, this acceleration (∼3-5 km s-2) is
very fast, while the velocities are in the common range for coronal
mass ejections. An interesting feature was a low-lying twisted second
filament near the erupting filament, which did not seem to participate
in the eruption. After the flare ribbons started on each of the second
filament’s sides, it seems to have untangled and vanished during the
flare. These observations are some of the highest resolution data of
an X-class flare to date and reveal some small-scale features yet to
be explained.

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Title: Measuring Elemental Abundances in Impulsive Heating Events
with EIS
Authors: Warren, Harry; Doschek, George A.; Young, Peter
2015TESS....121306W Altcode:
It is well established that elemental abundances vary in the solar
atmosphere and that this variation is organized by first ionization
potential (FIP). Previous studies have indicated that in the solar
corona low FIP elements, such as Fe, Si, and Mg, are enriched relative
to high FIP elements, such as H, He, C, N, and O. In this paper we
report on measurements of plasma composition made during transient
heating events observed at transition region temperatures with the
Extreme Ultraviolet Imaging Spectrometer (EIS) on Hinode. During these
events the intensities of O IV, V, and VI emission lines are enhanced
relative to emission lines from Mg V, VI, and VII and indicate a
composition close to that of the photosphere. Differential emission
measure calculations show a broad distribution of temperatures in
these events. Long-lived coronal structures, in contrast, show an
enrichment of low FIP elements and relatively narrow temperature
distributions. We conjecture that plasma composition is an important
signature of the coronal heating process, with impulsive heating
leading to the evaporation of unfractionated material from the lower
layers of the solar atmosphere and higher frequency heating leading
to the accumulation of low-FIP elements in the corona.

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Title: Dark Jets in Solar Coronal Holes
Authors: Young, Peter R.
2015ApJ...801..124Y Altcode: 2015arXiv150102751Y
A new solar feature termed a dark jet is identified from observations
of an extended solar coronal hole that was continuously monitored
for over 44 hr by the Extreme Ultraviolet Imaging Spectrometer on
board the Hinode spacecraft in 2011 February 8-10 as part of Hinode
Operation Plan No. 177 (HOP 177). Line of sight (LOS) velocity maps
derived from the coronal Fe xii λ195.12 emission line, formed at
1.5 MK, revealed a number of large-scale, jet-like structures that
showed significant blueshifts. The structures had either weak or no
intensity signal in 193 Å filter images from the Atmospheric Imaging
Assembly on board the Solar Dynamics Observatory, suggesting that
the jets are essentially invisible to imaging instruments. The dark
jets are rooted in bright points and occur both within the coronal
hole and at the quiet Sun-coronal hole boundary. They exhibit a wide
range of shapes, from narrow columns to fan-shaped structures, and
sometimes multiple jets are seen close together. A detailed study
of one dark jet showed LOS speeds increasing along the jet axis from
52 to 107 km s-1 and a temperature of 1.2-1.3 MK. The low
intensity of the jet was due either to a small filling factor of 2%
or to a curtain-like morphology. From the HOP 177 sample, dark jets
are as common as regular coronal hole jets, but their low intensity
suggests a mass flux around two orders of magnitude lower.

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Title: Piezoelectric Dust Detector Design and Calibration for the
Armadillo Program
Authors: Odom, F.; Richter, G.; Brown, J.; Martinsen, B.; Cai, R.;
Fellows, M.; Wolf, A.; Montag, C.; Young, P.; Carmona-Reyes, J. A.;
Schmoke, J.; Cook, M.; Garner, B.; Gravagne, I.; Pin, K.; Shedd, L.;
Groskreutz, T.; Hegle, T.; Mulenos, N.; Stone, J.; Wiley, C.; Yanga,
V.; Eustice, D.; Flachsbart, K.; Steele, N.; Tilley, C.; Friudenberg,
P.; Penshorn, D.; Henderson, L.; Cavazos, E.; Nabili, A.; Cox, E.;
Cox, A.; Wood, J.; Devine, L.; Curran, J.; Mendiola, A.; Falkner, C.;
Laufer, R.; Srama, R.; Schubert, K. E.; Matthews, L. S.; Lightsey,
G.; Hyde, T. W.
2015LPI....46.2191O Altcode: 2015LPICo1832.2191O
Design and calibration of piezoelectric dust detector for LEO.

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Title: The 2014 March 29 X-flare: Subarcsecond Resolution Observations
of Fe XXI λ1354.1
Authors: Young, Peter R.; Tian, Hui; Jaeggli, Sarah
2015ApJ...799..218Y Altcode: 2014arXiv1409.8603Y
The Interface Region Imaging Spectrometer (IRIS) is the first solar
instrument to observe ~10 MK plasma at subarcsecond spatial resolution
through imaging spectroscopy of the Fe XXI λ1354.1 forbidden line. IRIS
observations of the X1 class flare that occurred on 2014 March 29 at
17:48 UT reveal Fe XXI emission from both the flare ribbons and the
post-flare loop arcade. Fe XXI appears at all of the chromospheric
ribbon sites, although typically with a delay of one raster (75 s) and
sometimes offset by up to 1”. 100-200 km s-1 blue-shifts
are found at the brightest ribbons, suggesting hot plasma upflow into
the corona. The Fe XXI ribbon emission is compact with a spatial
extent of &lt;2”, and can extend beyond the chromospheric ribbon
locations. Examples are found of both decreasing and increasing
blue-shift in the direction away from the ribbon locations, and
blue-shifts were present for at least six minutes after the flare
peak. The post-flare loop arcade, seen in Atmospheric Imaging Assembly
131 Å filtergram images that are dominated by Fe XXI, exhibited
bright loop-tops with an asymmetric intensity distribution. The sizes
of the loop-tops are resolved by IRIS at &gt;=1”, and line widths
in the loop-tops are not broader than in the loop-legs suggesting the
loop-tops are not sites of enhanced turbulence. Line-of-sight speeds
in the loop arcade are typically &lt;10 km s-1, and mean
non-thermal motions fall from 43 km s-1 at the flare peak
to 26 km s-1 six minutes later. If the average velocity
in the loop arcade is assumed to be at rest, then it implies a new
reference wavelength for the Fe XXI line of 1354.106 ± 0.023 Å.

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Title: A coronal hole jet observed with Hinode and the Solar Dynamics
Observatory
Authors: Young, Peter R.; Muglach, Karin
2014PASJ...66S..12Y Altcode: 2014PASJ..tmp..106Y; 2014arXiv1402.4389Y; 2014PASJ...66..S12Y
A small blowout jet was observed at the boundary of the south polar
coronal hole on 2011 February 8 at around 21:00 UT. Images from
the Atmospheric Imaging Assembly (AIA) on board the Solar Dynamics
Observatory (SDO) revealed an expanding loop rising from one footpoint
of a compact, bipolar bright point. Magnetograms from the Helioseismic
Magnetic Imager (HMI) on board SDO showed that the jet was triggered
by the cancelation of a parasitic positive polarity feature near
the negative pole of the bright point. The jet emission was present
for 25 min and it extended 30 Mm from the bright point. Spectra from
the Extreme Ultraviolet Imaging Spectrometer on board Hinode yielded
a temperature and density of 1.6 MK and 0.9-1.7 × 108
cm-3 for the ejected plasma. Line-of-sight velocities reached
up to 250 km s-1 and were found to increase with height,
suggesting plasma acceleration within the body of the jet. Evidence
was found for twisting motions within the jet based on variations of
the line-of-sight velocities across the jet width. The derived angular
speed was in the range (9-12) × 10-3 rad s-1,
consistent with previous measurements from jets. The density of the
bright point was 7.6 × 108 cm-3, and the peak
of the bright point's emission measure occurred at 1.3 MK, with no
plasma above 3 MK.

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Title: The VAULT2.0 Observing Campaign: A Comprehensive Investigation
of the Chromosphere-Corona Interface at Sub-arcsecond scales
Authors: Vourlidas, A.; Korendyke, C.; Tun-Beltran, S. D.; Ugarte-Urra,
I.; Morrill, J. S.; Warren, H. P.; Young, P.; De Pontieu, B.; Gauzzi,
G.; Reardon, K.
2014AGUFMSH41C4155V Altcode:
We report the first results from an observing campaign in support of
the VAULT2.0 sounding rocket launch on September 30, 2014. VAULT2.0
is a Lya (1216Å) spectroheliograph capable of 0.3" (~250 km) spatial
resolution. The objective of the VAULT2.0 project is the study of
the chromosphere-corona interface. This interface has acquired renewed
emphasis over the last few years, thanks to high-resolution observations
from Hinode/SOT and EIS instruments and the Lya imaging from the two
VAULT flights. The observations have shown that the upper chromosphere
may play a more important role in heating the corona and in affecting
EUV observations that previously thought: (1) by supplying the mass
via Type-II spicules and, (2) by absorbing coronal emission. Many of
the required clues for further progress are located in sub-arcsecond
structures with temperatures between 10000 and 50000 K, a regime not
accessible by Hinode or SDO. Lyman-alpha observations are, therefore,
ideal, for filling in this gap. The observing campaign in support of
the VAULT2.0 is closely coordinated with the Hinode and IRIS missions
to study the mass/energy flow from the chromosphere to the corona with
joint observations of type-II spicules, and the magnetic connectivity
of coronal loops using the full imaging and spectral capabilities of
IRIS, Hinode and SDO. Several ground-based observatories also provide
important observations (IBIS, BBSO, SOLIS). The VAULT2.0 project is
funded by the NASA LCAS program.

---------------------------------------------------------
Title: The 2014 March 29 X-Flare: Results from the Best-Ever Flare
Observation
Authors: Young, P.
2014AGUFMSH53D..01Y Altcode:
An X1 class solar flare occurred on 2014 March 29, peaking at 17:48
UT, and producing a filament eruption and EUV wave. It was observed
as part of a Sac Peak-IRIS-Hinode observing program, delivering
unprecedented coverage at all layers of the solar atmosphere. This talk
will summarize new results obtained for this flare, with a particular
focus on spectroscopic results obtained from IRIS and Hinode/EIS. Topics
include mass flows prior and during the filament eruption, dynamics
of 10 MK plasma during the flare rise phase, and the evolution of the
flare ribbons

---------------------------------------------------------
Title: Solar Dynamics Observatory and Hinode Observations of a
Blowout Jet in a Coronal Hole
Authors: Young, P. R.; Muglach, K.
2014SoPh..289.3313Y Altcode: 2013arXiv1309.7324Y; 2014SoPh..tmp...24Y
A blowout jet occurred within the south coronal hole on 9 February
2011 at 09:00 UT and was observed by the Atmospheric Imaging Assembly
(AIA) and Helioseismic and Magnetic Imager (HMI) onboard the Solar
Dynamics Observatory, and by the EUV Imaging Spectrometer (EIS)
and X-Ray Telescope (XRT) onboard the Hinode spacecraft during
coronal-hole monitoring performed as part of Hinode Operations
Program No. 177. Images from AIA show expanding hot and cold loops
from a small bright point with plasma ejected in a curtain up to 30 Mm
wide. The initial intensity front of the jet had a projected velocity
of 200 km s−1, and the line-of-sight (LOS) velocities
measured by EIS are between 100 and 250 km s−1. The LOS
velocities increased along the jet, implying that an acceleration
mechanism operates within the body of the jet. The jet plasma had a
density of 2.7×108 cm−3 and a temperature of
1.4 MK. During the event a number of bright kernels were seen at the
base of the bright point. The kernels have sizes of ≈ 1000 km, are
variable in brightness, and have lifetimes of 1 - 15 minutes. An XRT
filter ratio yields temperatures of 1.5 - 3.0 MK for the kernels. The
bright point existed for at least ten hours, but disappeared within
two hours after the jet, which lasted for 30 minutes. HMI data reveal
converging photospheric flows at the location of the bright point,
and the mixed-polarity magnetic flux canceled over a period of four
hours on either side of the jet.

---------------------------------------------------------
Title: Intense active region brightenings observed by IRIS
Authors: Young, Peter R.
2014AAS...22430202Y Altcode:
Active region raster scans obtained with the Interface Region
Imaging Spectrometer (IRIS) typically reveal a few extremely intense
brightenings in the Si IV emission lines (formed around 80,000 K) that
are not related to flares. The brightenings are around 0.5-1.0 arcsec
(0.4-0.8 Mm) in size, and the line profiles can be very broad (up to
300 km/s), showing multiple emission components. Similar brightenings
were reported from the Coronal Diagnostic Spectrometer (CDS) on board
the Solar and Heliospheric Observatory (SOHO) and were termed active
region blinkers. The much higher spatial and spectral resolution of IRIS
together with high cadence coronal and photospheric imaging from the
Solar Dynamics Observatory allows the brightenings to be identified
with magnetic field and coronal signatures. Example events will be
shown and statistics given.

---------------------------------------------------------
Title: Temporal Evolution of Solar Wind Ion Composition and their
Source Coronal Holes During the Declining Phase of Cycle 23
Authors: Ko, Yuan-Kuen; Muglach, Karin; Wang, Yi-Ming; Young, Peter
R.; Lepri, Susan T.
2014AAS...22432366K Altcode:
We present our analysis of the temporal trend in the solar wind
(SW) ion charge states and the properties in the associated source
coronal holes (CHs) during the declining phase of solar cycle 23. We
find that the SW ions exhibit a trend of decreasing ionization state
with time, consistent with previous studies. However the rate of
decrease is different between the slow and fast SW. The photospheric
magnetic field strength in both regions is found to exhibit similar
trend of decrease with time. On the other hand, the temporal trend is
different in the line emissions from different layers of the atmosphere
(chromosphere, transit region and corona). Within each CH, the coronal
emission generally increases toward the boundary of the CH as the
underlying photospheric magnetic field strength increases, the net
unbalanced field strength decreases and the magnetic field becomes
less unipolar. But the coronal emission averaged over the entire CH
area does not have appreciable change with time. We find that ions
which freeze-in at lower altitude in the corona, such as C and O ions,
have a stronger correlation between their ionization state and the
average photospheric magnetic field strength in the slow SW, while Fe
ions which freeze-in at higher altitude have a stronger correlation
in the fast SW. Our analyses provide important clues for how the SW is
formed, heated and accelerated in response to the long-term evolution
of the solar magnetic field at its source coronal hole.

---------------------------------------------------------
Title: Temporal Evolution of Solar Wind Ion Composition and
their Source Coronal Holes during the Declining Phase of Cycle
23. I. Low-latitude Extension of Polar Coronal Holes
Authors: Ko, Yuan-Kuen; Muglach, Karin; Wang, Yi-Ming; Young, Peter
R.; Lepri, Susan T.
2014ApJ...787..121K Altcode:
We analyzed 27 solar wind (SW) intervals during the declining phase
of cycle 23, whose source coronal holes (CHs) can be unambiguously
identified and are associated with one of the polar CHs. We found that
the SW ions have a temporal trend of decreasing ionization state,
and such a trend is different between the slow and fast SW. The
photospheric magnetic field, both inside and at the outside boundary
of the CH, also exhibits a trend of decrease with time. However,
EUV line emissions from different layers of the atmosphere exhibit
different temporal trends. The coronal emission inside the CH generally
increases toward the CH boundary as the underlying field increases in
strength and becomes less unipolar. In contrast, this relationship is
not seen in the coronal emission averaged over the entire CH. For C
and O SW ions that freeze-in at lower altitude, stronger correlation
between their ionization states and field strength (both signed and
unsigned) appears in the slow SW, while for Fe ions that freeze-in
at higher altitude, stronger correlation appears in the fast SW. Such
correlations are seen both inside the CH and at its boundary region. On
the other hand, the coronal electron temperature correlates well with
the SW ion composition only in the boundary region. Our analyses,
although not able to determine the likely footpoint locations of the
SW of different speeds, raise many outstanding questions for how the
SW is heated and accelerated in response to the long-term evolution
of the solar magnetic field.

---------------------------------------------------------
Title: Photospheric Signatures of Coronal Hole Jets
Authors: Muglach, Karin; Young, Peter R.
2014AAS...22432333M Altcode:
Coronal jets are transient, collimated ejections of plasma that are
a common feature of solar X-ray and EUV image sequences. Of special
interest is the contribution that coronal hole jets make to the
solar wind outflow. A new class of coronal hole jets, termed "dark
jets", has been identified with the EUV Imaging Spectrometer (EIS)
on board Hinode. The jets are identified in EUV spectral lines with
line-of-sight velocities of 50-100 km/s and enhanced line widths, yet
they show little or no intensity signature in image sequences from the
Atmospheric Imaging Assembly on board the Solar Dynamics Observatory
(SDO) or the X-Ray Telescope on board Hinode.In this contribution we
will investigate the photosphere at the footpoint of these jets. White
light images from the Helioseismic Magnetic Imager (HMI) on board SDO
are used to derive the plane-of-sky flow field using local correlation
tracking, and HMI magnetograms show the evolution of the magnetic
flux. Both the evolution of the magnetic field and flows allow us to
study the photospheric driver of these jets.

---------------------------------------------------------
Title: Assessing atomic data accuracy along isoelectronic sequences
Authors: Young, Peter R.; Feldman, Uri
2014AAS...22410603Y Altcode:
The CHIANTI atomic database provides radiative decay rates and electron
excitation rates for modeling collisionally-excited emission lines from
242 ions. We present a new method for assessing atomic data accuracy
whereby level populations for specific atomic levels are plotted
along isoelectronic sequences. Results are presented for the helium
through fluorine isoelectronic sequences. Generally a smooth variation
of population with atomic number is found and so anomalies, often due
to problems with atomic data, can be identified. One exception is for
the iron ions, which can show level populations an order of magnitude
larger than neighboring ions. These can be demonstrated to be due to
the much larger atomic models that are typically run for iron ions.

---------------------------------------------------------
Title: Core and Wing Densities of Asymmetric Coronal Spectral
Profiles: Implications for the Mass Supply of the Solar Corona
Authors: Patsourakos, S.; Klimchuk, J. A.; Young, P. R.
2014ApJ...781...58P Altcode: 2013arXiv1312.4842P
Recent solar spectroscopic observations have shown that coronal spectral
lines can exhibit asymmetric profiles, with enhanced emissions at their
blue wings. These asymmetries correspond to rapidly upflowing plasmas
at speeds exceeding ≈50 km s-1. Here, we perform a study
of the density of the rapidly upflowing material and compare it with
that of the line core that corresponds to the bulk of the plasma. For
this task, we use spectroscopic observations of several active regions
taken by the Extreme Ultraviolet Imaging Spectrometer of the Hinode
mission. The density sensitive ratio of the Fe XIV lines at 264.78 and
274.20 Å is used to determine wing and core densities. We compute the
ratio of the blue wing density to the core density and find that most
values are of order unity. This is consistent with the predictions for
coronal nanoflares if most of the observed coronal mass is supplied
by chromospheric evaporation driven by the nanoflares. However,
much larger blue wing-to-core density ratios are predicted if most of
the coronal mass is supplied by heated material ejected with type II
spicules. Our measurements do not rule out a spicule origin for the
blue wing emission, but they argue against spicules being a primary
source of the hot plasma in the corona. We note that only about 40%
of the pixels where line blends could be safely ignored have blue wing
asymmetries in both Fe XIV lines. Anticipated sub-arcsecond spatial
resolution spectroscopic observations in future missions could shed
more light on the origin of blue, red, and mixed asymmetries.

---------------------------------------------------------
Title: Evidence for Two Separate Heliospheric Current Sheets of
Cylindrical Shape During Mid-2012
Authors: Wang, Y. -M.; Young, P. R.; Muglach, K.
2014ApJ...780..103W Altcode:
During the reversal of the Sun's polar fields at sunspot maximum,
outward extrapolations of magnetograph measurements often predict the
presence of two or more current sheets extending into the interplanetary
medium, instead of the single heliospheric current sheet (HCS) that
forms the basis of the standard "ballerina skirt" picture. By comparing
potential-field source-surface models of the coronal streamer belt
with white-light coronagraph observations, we deduce that the HCS
was split into two distinct structures with circular cross sections
during mid-2012. These cylindrical current sheets were centered near
the heliographic equator and separated in longitude by roughly 180° a
corresponding four-sector polarity pattern was observed at Earth. Each
cylinder enclosed a negative-polarity coronal hole that was identifiable
in extreme ultraviolet images and gave rise to a high-speed stream. The
two current sheet systems are shown to be a result of the dominance
of the Sun's nonaxisymmetric quadrupole component, as the axial dipole
field was undergoing its reversal during solar cycle 24.

---------------------------------------------------------
Title: Major updates to the CHIANTI atomic database for the astronomy
community
Authors: Young, Peter
2014adap.prop...38Y Altcode:
CHIANTI is a critically-assessed, freely-available atomic database
and software package that is widely-used for the interpretation and
analysis of astronomical data. A three-year project is proposed to
modernize the CHIANTI infrastructure (software code and methods,
and data formats), include new atomic data and processes, add new
software capability and write new documentation. These improvements will
provide more accurate atomic data and new capabilities specifically
for the astrophysics community, enabling new and expanded analyzes
of data from NASA-supported missions that will directly address some
of the most important NASA science goals: exploring galaxy evolution,
understanding the nature of black holes, and determining the origins
of stars. High quality atomic data are fundamental to all aspects of
astrophysics, and the accuracy of the assessed atomic data in CHIANTI is
recognized by the makers of other astrophysics plasma codes, including
CLOUDY, APED, XSTAR and MOCASSIN who incorporate the data into their
models. The proposed CHIANTI updates therefore indirectly benefit many
other astronomers. The specific enhancements that will be made are: 1. a
new method for assessing and storing electron excitation that will give
improved accuracy at low temperatures suitable for photoionized plasmas;
2. faster software calculations and data reading necessary to include
larger (1000's of levels) atomic models; 3. modernize aging IDL code,
aligning it with the newer Python code; 4. add new atomic data for the
iron peak elements, forbidden lines, and key isoelectronic sequences;
5. perform and publish the first ever benchmark study of visible and
ultraviolet forbidden line diagnostics; 6. greatly expand recombination
line models for X-ray applications; 7. interface the database to a
state-of-the-art emission line fitting package; and 8. create new
technical documentation describing all aspects of the database.

---------------------------------------------------------
Title: Progress toward high resolution EUV spectroscopy
Authors: Korendyke, C.; Doschek, G. A.; Warren, H.; Young, P. R.;
Chua, D.; Hassler, D. M.; Landi, E.; Davila, J. M.; Klimchuck, J.;
Tun, S.; DeForest, C.; Mariska, J. T.; Solar C Spectroscopy Working
Group; LEMUR; EUVST Development Team
2013SPD....44..143K Altcode:
HIgh resolution EUV spectroscopy is a critical instrumental technique
to understand fundamental physical processes in the high temperature
solar atmosphere. Spectroscopic observations are used to measure
differential emission measure, line of sight and turbulent flows,
plasma densities and emission measures. Spatially resolved, spectra of
these emission lines with adequate cadence will provide the necessary
clues linking small scale structures with large scale, energetic
solar phenomena. The necessary observations to determine underlying
physical processes and to provide comprehensive temperature coverage
of the solar atmosphere above the chromosphere will be obtained by the
proposed EUVST instrument for Solar C. This instrument and its design
will be discussed in this paper. Progress on the VEry high Resolution
Imaging Spectrograph (VERIS) sounding rocket instrument presently under
development at the Naval Research Laboratory will also be discussed.

---------------------------------------------------------
Title: A Spectroscopic Survey of Coronal Hole Jets
Authors: Young, Peter R.; Muglach, K.
2013SPD....44...19Y Altcode:
Coronal hole jets have been suggested to make a significant contribution
to the solar wind, but spectroscopic measurements - which provide
the best means of measuring the mass flux - have been rare due to
the difficulty of capturing jets with narrow slit spectrometers. A
continuous two day coronal hole measurement made with the Hinode/EIS
instrument is reported, which has revealed over 30 jets seen in
the coronal Fe XII 195.12 (1.5 MK) emission line. More than half of
the events have no clear signature in SDO/AIA or Hinode/XRT images
and thus represent a separate class of jet events not previously
reported. The jets show a wide range of morphologies, ranging from
classic columnar features to mini-CME events. Statistics of the events
will be presented: their relation to bright points and the coronal hole
boundary; durations; and repeated occurrence. Velocity, density and
temperature measurements derived from the EIS spectra will be presented,
and mass flux estimated. The photospheric signatures of the jets,
as determined from SDO/HMI, will be shown in a separate presentation
(Muglach &amp; Young).

---------------------------------------------------------
Title: Photospheric signatures of coronal hole jets
Authors: Muglach, Karin; Young, P. R.
2013SPD....44...20M Altcode:
Jets in EUV and X-ray images have been observed for several
decades. Many of them originate in coronal holes which have received
special interest as possible contributors to the solar wind. A new
class of CH jets are observed with Hinode/EIS which show pronounced
signatures in EUV spectral lines. Coronal velocities of up to 200 km/s
and enhancements in line width are measured. On the other hand these
jets are hardly visible in imaging data like SDO/AIA and Hinode/XRT
(see contribution by Young and Muglach). In this contribution we
will investigate the photospheric signatures at the footpoint of
these jets. We use SDO/HMI magnetograms to show the evolution of the
magnetic flux. From SDO white light images we derive the plane-of-sky
flow field using local correlation tracking. Both the evolution of
the magnetic field and the flows allow us to study the photospheric
drivers of these jets.

---------------------------------------------------------
Title: Properties of a Solar Flare Kernel Observed by Hinode and SDO
Authors: Young, P. R.; Doschek, G. A.; Warren, H. P.; Hara, H.
2013ApJ...766..127Y Altcode: 2012arXiv1212.4388Y
Flare kernels are compact features located in the solar chromosphere
that are the sites of rapid heating and plasma upflow during the rise
phase of flares. An example is presented from a M1.1 class flare in
active region AR 11158 observed on 2011 February 16 07:44 UT for which
the location of the upflow region seen by EUV Imaging Spectrometer (EIS)
can be precisely aligned to high spatial resolution images obtained by
the Atmospheric Imaging Assembly (AIA) and Helioseismic and Magnetic
Imager (HMI) on board the Solar Dynamics Observatory (SDO). A string
of bright flare kernels is found to be aligned with a ridge of strong
magnetic field, and one kernel site is highlighted for which an upflow
speed of ≈400 km s-1 is measured in lines formed at 10-30
MK. The line-of-sight magnetic field strength at this location is
≈1000 G. Emission over a continuous range of temperatures down to
the chromosphere is found, and the kernels have a similar morphology
at all temperatures and are spatially coincident with sizes at the
resolution limit of the AIA instrument (lsim400 km). For temperatures
of 0.3-3.0 MK the EIS emission lines show multiple velocity components,
with the dominant component becoming more blueshifted with temperature
from a redshift of 35 km s-1 at 0.3 MK to a blueshift of
60 km s-1 at 3.0 MK. Emission lines from 1.5-3.0 MK show a
weak redshifted component at around 60-70 km s-1 implying
multi-directional flows at the kernel site. Significant non-thermal
broadening corresponding to velocities of ≈120 km s-1 is
found at 10-30 MK, and the electron density in the kernel, measured
at 2 MK, is 3.4 × 1010 cm-3. Finally, the Fe
XXIV λ192.03/λ255.11 ratio suggests that the EIS calibration has
changed since launch, with the long wavelength channel less sensitive
than the short wavelength channel by around a factor two.

---------------------------------------------------------
Title: Chromospheric Evaporation in an M1.8 Flare Observed by the
Extreme-ultraviolet Imaging Spectrometer on Hinode
Authors: Doschek, G. A.; Warren, H. P.; Young, P. R.
2013ApJ...767...55D Altcode: 2012arXiv1212.4027D
We discuss observations of chromospheric evaporation for a complex
flare that occurred on 2012 March 9 near 03:30 UT obtained from the
Extreme-ultraviolet Imaging Spectrometer (EIS) on board the Hinode
spacecraft. This was a multiple event with a strong energy input
that reached the M1.8 class when observed by EIS. EIS was in raster
mode and fortunately the slit was almost at the exact location of
a significant energy input. Also, EIS obtained a full-CCD spectrum
of the flare, i.e., the entire CCD was readout so that data were
obtained for about the 500 lines identified in the EIS wavelength
ranges. Chromospheric evaporation characterized by 150-200 km
s-1 upflows was observed in multiple locations in
multi-million degree spectral lines of flare ions such as Fe XXII,
Fe XXIII, and Fe XXIV, with simultaneous 20-60 km s-1
upflows in million degree coronal lines from ions such as Fe XII-Fe
XVI. The behavior of cooler, transition region ions such as O VI, Fe
VIII, He II, and Fe X is more complex, but upflows were also observed
in Fe VIII and Fe X lines. At a point close to strong energy input in
space and time, the flare ions Fe XXII, Fe XXIII, and Fe XXIV reveal
an isothermal source with a temperature close to 14 MK and no strong
blueshifted components. At this location there is a strong downflow
in cooler active region lines from ions such as Fe XIII and Fe XIV,
on the order of 200 km s-1. We speculate that this downflow
may be evidence of the downward shock produced by reconnection in the
current sheet seen in MHD simulations. A sunquake also occurred near
this location. Electron densities were obtained from density sensitive
lines ratios from Fe XIII and Fe XIV. Atmospheric Imaging Assembly
(AIA) observations from the Solar Dynamics Observatory are used with
JHelioviewer to obtain a qualitative overview of the flare. However,
AIA data are not presented in this paper. In summary, spectroscopic data
from EIS are presented that can be used for predictive tests of models
of chromospheric evaporation as envisaged in the Standard Flare Model.

---------------------------------------------------------
Title: Flare Footpoint Regions Observed by the Extreme-ultraviolet
Imaging Spectrometer (EIS) on Hinode
Authors: Doschek, G. A.; Warren, H. P.; Young, P. R.; Caspi, A.
2013enss.confE..74D Altcode:
The Extreme-ultraviolet Imaging Spectrometer (EIS) on Hinode has
observed flare footpoints using a variety of studies designed to
observe various aspects of the solar flare Standard Model. Some of
these observations are accompanied by imaging data from RHESSI. We
present observations of upflows in flare footpoint regions obtained
from picket-fence raster observations of two flares that occurred
on 24 and 25 September 2011. The observations consist of upflow and
non-thermal speeds at various temperatures (from about 1 MK to 15
MK) at footpoint regions as well as a limited differential emission
measure. RHESSI observations provide constraints on the energetic
electron precipitation into the footpoints. Electron densities are
available from an Fe XIV ratio, and SDO AIA data are also investigated
for context. The RHESSI energy input will be assessed in terms of 1D
models of the footpoint regions.

---------------------------------------------------------
Title: CHIANTI 7.1: a new database release for SDO data analysis
Authors: Young, P. R.; Landi, E.; Del Zanna, G.; Dere, K. P.; Mason,
H. E.
2013enss.confE..58Y Altcode:
Version 7.1 of the CHIANTI atomic database was released in October 2012
and contains a number of improvements to better model data returned by
the AIA and EVE instruments on board SDO. Specifically the models for
the important iron ions Fe VIII to Fe XIV have been greatly expanded,
yielding many thousands of new transitions in the 50-170 angstrom
range that enable the irradiance spectra obtained by EVE to be modeled
more accurately. A lack of available atomic data meant that the AIA 94
angstrom channel was not well modeled at low temperatures in earlier
versions of CHIANTI. New data for Fe VIII, Fe X and Fe XIV added to
CHIANTI 7.1 give important contributions to the channel and greatly
improve comparisons with theory.

---------------------------------------------------------
Title: SDO and Hinode observations of coronal heating at a flare
kernel site
Authors: Young, P. R.; Doschek, G. A.; Warren, H. P.; Hara, H.
2013enss.confE..36Y Altcode:
Flare kernels are compact features located in the chromosphere that
are the sites of rapid heating and plasma upflow during the rise phase
of flares. They provide an excellent opportunity for testing models of
energy transport and dissipation in the solar atmosphere as they are
very bright and emit over a wide temperature range. A M1.1 class flare
that peaked at 07:44 UT on 2011 February 16 was observed simultaneously
by SDO and Hinode, and one flare kernel observed prior to the flare
peak is highlighted. It is found to emit at all temperatures from
the chromosphere through to 30 MK, with all AIA channels brightening
simultaneously and rise times of only 1 minute. The kernel is located on
a ridge of strong magnetic field close to a neutral line in the active
region. The kernel is at the resolution limit of AIA, suggesting a size
of &lt; 0.6 arcsec. Hinode/EIS allows velocity patterns in the kernel
to be tracked over a wide temperature range and reveals a dominant high
speed upflow of 400 km/s at temperatures of 10-30 MK, with both down
and upflows measured at cooler temperatures of 1.5-3.0 MK, suggesting
unresolved structures. All emission lines show evidence of significant
non-thermal broadening, and the electron density of the plasma is 3.4
x 10^10 cm-3. The observations are compared to models of chromospheric
evaporation and similarities and differences are highlighted.

---------------------------------------------------------
Title: The velocity signature of coronal jets as observed with
Hinode/EIS
Authors: Muglach, K.; Young, P. R.
2013enss.confE..59M Altcode:
In this contribution we show preliminary results of a study of jets
in coronal holes. We use Hinode/EIS to investigate the spectroscopic
signatures of the jets and SDO/AIA and HMI to derive additional
information on the plasma and magnetic field evolution. EIS was
scanning a low latitude coronal hole and tracking it for about 2
days as it rotated over the solar disk. The coronal jets are best
revealed through Doppler and line width maps of Fe XII 195.1 A (formed
at 1.5 MK), and have sizes of 10-100 arcsec. Higher spatial and time
resolution is provided by SDO: coronal and chromospheric images from
AIA show the time evolution of the jet and line-of-sight magnetograms
show the evolution of the magnetic footpoints of the jet. We present
several examples of these extended jets and describe their properties
as derived from the diagnostics we have available.

---------------------------------------------------------
Title: CHIANTI—An Atomic Database for Emission Lines. XIII. Soft
X-Ray Improvements and Other Changes
Authors: Landi, E.; Young, P. R.; Dere, K. P.; Del Zanna, G.; Mason,
H. E.
2013ApJ...763...86L Altcode:
The CHIANTI spectral code consists of two parts: an atomic database
and a suite of computer programs in Python and IDL. Together, they
allow the calculation of the optically thin spectrum of astrophysical
objects and provide spectroscopic plasma diagnostics for the analysis
of astrophysical spectra. The database includes atomic energy levels,
wavelengths, radiative transition probabilities, collision excitation
rate coefficients, ionization, and recombination rate coefficients,
as well as data to calculate free-free, free-bound, and two-photon
continuum emission. Version 7.1 has been released, which includes
improved data for several ions, recombination rates, and element
abundances. In particular, it provides a large expansion of the
CHIANTI models for key Fe ions from Fe VIII to Fe XIV to improve the
predicted emission in the 50-170 Å wavelength range. All data and
programs are freely available at http://www.chiantidatabase.org and
in SolarSoft, while the Python interface to CHIANTI can be found at
http://chiantipy.sourceforge.net.

---------------------------------------------------------
Title: A Long-Lived Equatorial Coronal Hole and the Associated
Solar Wind
Authors: Ko, Y.; Young, P. R.; Muglach, K.; Wang, Y.; Lepri, S. T.;
Laming, J. M.; Popecki, M.
2012AGUFMSH53A2261K Altcode:
We study an equatorial coronal hole that came back rotation after
rotation in a course of eight months from July 2007 to March 2008. This
coronal hole was also one of the source regions of the solar wind
measured by ACE during this period. The associated solar wind speed
profiles for the 10 solar rotations are similar that start with a fast
wind above 600 km/s and gradually lower down to below 400 km/s. The ion
composition data indicate a decreasing trend in the ionization states
of heavy ions, especially for the Fe ions. This recurring coronal hole
presents a good opportunity for studying the relations between the solar
wind at a range of speeds and the solar source that produces it. We
present a detailed study of the solar wind from this coronal hole,
concentrating on the ion charge and elemental composition properties,
and the variation in the magnetic and spectroscopic properties in this
source coronal hole. We discuss implications in the solar wind formation
based on the relations between these properties of the source coronal
hole and the associated solar wind.

---------------------------------------------------------
Title: LEMUR: Large European module for solar Ultraviolet
Research. European contribution to JAXA's Solar-C mission
Authors: Teriaca, Luca; Andretta, Vincenzo; Auchère, Frédéric;
Brown, Charles M.; Buchlin, Eric; Cauzzi, Gianna; Culhane, J. Len;
Curdt, Werner; Davila, Joseph M.; Del Zanna, Giulio; Doschek, George
A.; Fineschi, Silvano; Fludra, Andrzej; Gallagher, Peter T.; Green,
Lucie; Harra, Louise K.; Imada, Shinsuke; Innes, Davina; Kliem,
Bernhard; Korendyke, Clarence; Mariska, John T.; Martínez-Pillet,
Valentin; Parenti, Susanna; Patsourakos, Spiros; Peter, Hardi; Poletto,
Luca; Rutten, Robert J.; Schühle, Udo; Siemer, Martin; Shimizu,
Toshifumi; Socas-Navarro, Hector; Solanki, Sami K.; Spadaro, Daniele;
Trujillo-Bueno, Javier; Tsuneta, Saku; Dominguez, Santiago Vargas;
Vial, Jean-Claude; Walsh, Robert; Warren, Harry P.; Wiegelmann,
Thomas; Winter, Berend; Young, Peter
2012ExA....34..273T Altcode: 2011ExA...tmp..135T; 2011arXiv1109.4301T
The solar outer atmosphere is an extremely dynamic environment
characterized by the continuous interplay between the plasma and the
magnetic field that generates and permeates it. Such interactions play a
fundamental role in hugely diverse astrophysical systems, but occur at
scales that cannot be studied outside the solar system. Understanding
this complex system requires concerted, simultaneous solar observations
from the visible to the vacuum ultraviolet (VUV) and soft X-rays, at
high spatial resolution (between 0.1” and 0.3”), at high temporal
resolution (on the order of 10 s, i.e., the time scale of chromospheric
dynamics), with a wide temperature coverage (0.01 MK to 20 MK,
from the chromosphere to the flaring corona), and the capability of
measuring magnetic fields through spectropolarimetry at visible and
near-infrared wavelengths. Simultaneous spectroscopic measurements
sampling the entire temperature range are particularly important. These
requirements are fulfilled by the Japanese Solar-C mission (Plan B),
composed of a spacecraft in a geosynchronous orbit with a payload
providing a significant improvement of imaging and spectropolarimetric
capabilities in the UV, visible, and near-infrared with respect to
what is available today and foreseen in the near future. The Large
European Module for solar Ultraviolet Research (LEMUR), described
in this paper, is a large VUV telescope feeding a scientific payload
of high-resolution imaging spectrographs and cameras. LEMUR consists
of two major components: a VUV solar telescope with a 30 cm diameter
mirror and a focal length of 3.6 m, and a focal-plane package composed
of VUV spectrometers covering six carefully chosen wavelength ranges
between 170 Å and 1270 Å. The LEMUR slit covers 280” on the Sun with
0.14” per pixel sampling. In addition, LEMUR is capable of measuring
mass flows velocities (line shifts) down to 2 km s - 1 or
better. LEMUR has been proposed to ESA as the European contribution
to the Solar C mission.

---------------------------------------------------------
Title: On VI Recombination Lines In Ultraviolet And Visible Spectra
Of Rr Telescopii
Authors: Young, Peter R.
2012AAS...22031901Y Altcode:
Nineteen recombination lines of O VI are identified in ultraviolet
and visible spectra of the symbiotic nova RR Telescopii at wavelengths
between 1122 and 6203 A. Only three of the lines have previously been
reported from astronomical spectra, and eight lines have never been
reported from either astronomical or laboratory spectra. The lines
represent transitions between levels with principal quantum numbers
up to 13 and the strongest lines by flux occur at 1124.82, 2070.90 and
3434.66 A, corresponding to transitions 4-5, 5-6 and 6-7. As the lines
are produced by recombination onto O VII they potentially allow O VII
emitting regions in astrophysical plasmas to be probed at ultraviolet
and visible wavelengths that otherwise can only be studied at X-ray
wavelengths.

---------------------------------------------------------
Title: Radiogenic heating in exoplanet systems
Authors: Carande, Bryce; Young, P.; McNamara, A.
2012AAS...22052503C Altcode:
We study the effect of variations in the amount of radiogenic
heating on the long-term thermal histories of exoplanets. The amount
of radiogenic heating experienced by a planet is dependent on the
abundance of long-lived radioisotopes (235U, 238U,
232Th, 40K) present in that stellar system. We
explain a method to constrain the uranium abundance of stellar systems
using more readily obtained measurements of europium absorption lines
in the host star, and present results from a preliminary set of stars
(including confirmed exoplanet hosts). We then use a parameterized
convection model to simulate the thermal evolution of planetary
mantles, given this variation in the abundance of radioisotopes
between systems. Our parameterized convection model is based on the
boundary layer theory, and includes a crustal heat flow parameter
as well as the assumption of a critical Rayleigh number needed for
convection. The simulated thermal evolution of a planet is found to
depend more on the choice of heat-flow parameters, and less on the
amount of radiogenic heating.

---------------------------------------------------------
Title: Hinode/EIS Flare Spectra During RHESSI Hard X-ray Bursts
Authors: Young, Peter R.; Warren, H.; Doschek, G.
2012AAS...22020442Y Altcode:
The standard flare model requires a beam of non-thermal electrons
- generated at the coronal flare site - to hit the chromosphere
and trigger heating and chromospheric evaporation. Ultraviolet
spectrometers allow the heated, evaporating plasma to be observed
and its properties measured. Observations of a M3 flare observed in
2011 September with Hinode/EIS, RHESSI and SDO/AIA will be presented,
revealing the physical conditions in the flare ribbons at the time of
the hard X-ray bursts. At the hottest temperatures (20 MK) upflowing
plasma with speeds up to 500 km/s are found co-spatial with stationary
plasma, while at cooler temperatures (0.5-2 MK) small downflows and
large non-thermal broadening are found. These observations will be
compared with predictions from multi-strand hydrodynamic simulations
that take the RHESSI-derived electron beam spectrum as input.

---------------------------------------------------------
Title: O VI Recombination Lines in Ultraviolet and Visible Spectra
of RR Telescopii
Authors: Young, P. R.
2012ApJ...749....1Y Altcode:
Nineteen recombination lines of O VI are identified in ultraviolet
and visible spectra of the symbiotic nova RR Telescopii at wavelengths
between 1122 and 6203 Å. Only three of the lines have previously been
reported from astronomical spectra, and eight lines have never been
reported from either astronomical or laboratory spectra. The lines
represent transitions between levels with principal quantum numbers
up to 13, and the strongest lines by flux occur at 1124.82, 2070.90,
and 3434.66 Å, corresponding to transitions 4-5, 5-6, and 6-7. As
the lines are produced by recombination onto O VII, they potentially
allow O VII emitting regions in astrophysical plasmas to be probed at
ultraviolet and visible wavelengths that otherwise can only be studied
at X-ray wavelengths.

---------------------------------------------------------
Title: UV spectroscopy with IRIS - experience learned from Hinode/EIS
Authors: Young, Peter
2012decs.confE.122Y Altcode:
IRIS will be the fourth in a sequence of solar ultraviolet
spectrometers, following on from CDS and SUMER on SOHO and
Hinode/EIS. The experience gained from these missions will be valuable
for ensuring that high quality science results emerge from IRIS right
from the beginning of the mission. This presentation will summarize
the experience gained from over five years of Hinode/EIS operations and
science, and identify where that experience may benefit the IRIS team.

---------------------------------------------------------
Title: CHIANTI—An Atomic Database for Emission Lines. XII. Version
7 of the Database
Authors: Landi, E.; Del Zanna, G.; Young, P. R.; Dere, K. P.; Mason,
H. E.
2012ApJ...744...99L Altcode:
The CHIANTI spectral code consists of an atomic database and
a suite of computer programs to calculate the optically thin
spectrum of astrophysical objects and carry out spectroscopic plasma
diagnostics. The database includes atomic energy levels, wavelengths,
radiative transition probabilities, collision excitation rate
coefficients, and ionization and recombination rate coefficients,
as well as data to calculate free-free, free-bound, and two-photon
continuum emission. Version 7 has been released, which includes
several new ions, significant updates to existing ions, as well as
Chianti-Py, the implementation of CHIANTI software in the Python
programming language. All data and programs are freely available at
http://www.chiantidatabase.org, while the Python interface to CHIANTI
can be found at http://chiantipy.sourceforge.net.

---------------------------------------------------------
Title: Velocity Measurements for a Solar Active Region Fan Loop from
Hinode/EIS Observations
Authors: Young, P. R.; O'Dwyer, B.; Mason, H. E.
2012ApJ...744...14Y Altcode: 2011arXiv1107.2362Y
The velocity pattern of a fan loop structure within a solar active
region over the temperature range 0.15-1.5 MK is derived using data from
the EUV Imaging Spectrometer (EIS) on board the Hinode satellite. The
loop is aligned toward the observer's line of sight and shows downflows
(redshifts) of around 15 km s-1 up to a temperature of 0.8
MK, but for temperatures of 1.0 MK and above the measured velocity
shifts are consistent with no net flow. This velocity result applies
over a projected spatial distance of 9 Mm and demonstrates that the
cooler, redshifted plasma is physically disconnected from the hotter,
stationary plasma. A scenario in which the fan loops consist of at
least two groups of "strands"—one cooler and downflowing, the other
hotter and stationary—is suggested. The cooler strands may represent
a later evolutionary stage of the hotter strands. A density diagnostic
of Mg VII was used to show that the electron density at around 0.8 MK
falls from 3.2 × 109 cm-3 at the loop base,
to 5.0 × 108 cm-3 at a projected height of
15 Mm. A filling factor of 0.2 is found at temperatures close to the
formation temperature of Mg VII (0.8 MK), confirming that the cooler,
downflowing plasma occupies only a fraction of the apparent loop
volume. The fan loop is rooted within a so-called outflow region that
displays low intensity and blueshifts of up to 25 km s-1 in
Fe XII λ195.12 (formed at 1.5 MK), in contrast to the loop's redshifts
of 15 km s-1 at 0.8 MK. A new technique for obtaining an
absolute wavelength calibration for the EIS instrument is presented and
an instrumental effect, possibly related to a distorted point-spread
function, that affects velocity measurements is identified.

---------------------------------------------------------
Title: Underflight Calibration of SOHO/CDS and Hinode/EIS with
EUNIS-07
Authors: Wang, Tongjiang; Thomas, Roger J.; Brosius, Jeffrey W.; Young,
Peter R.; Rabin, Douglas M.; Davila, Joseph M.; Del Zanna, Giulio
2011ApJS..197...32W Altcode: 2011arXiv1109.6598W
Flights of Goddard Space Flight Center's Extreme Ultraviolet
Normal Incidence Spectrograph (EUNIS) sounding rocket in 2006
and 2007 provided updated radiometric calibrations for Solar and
Heliospheric Observatory/Coronal Diagnostic Spectrometer (SOHO/CDS)
and Hinode/Extreme Ultraviolet Imaging Spectrometer (Hinode/EIS). EUNIS
carried two independent imaging spectrographs covering wavebands of
300-370 Å in first order and 170-205 Å in second order. After each
flight, end-to-end radiometric calibrations of the rocket payload were
carried out in the same facility used for pre-launch calibrations of
CDS and EIS. During the 2007 flight, EUNIS, SOHO/CDS, and Hinode/EIS
observed the same solar locations, allowing the EUNIS calibrations to
be directly applied to both CDS and EIS. The measured CDS NIS 1 line
intensities calibrated with the standard (version 4) responsivities with
the standard long-term corrections are found to be too low by a factor
of 1.5 due to the decrease in responsivity. The EIS calibration update
is performed in two ways. One uses the direct calibration transfer of
the calibrated EUNIS-07 short wavelength (SW) channel. The other uses
the insensitive line pairs, in which one member was observed by the
EUNIS-07 long wavelength (LW) channel and the other by EIS in either the
LW or SW waveband. Measurements from both methods are in good agreement,
and confirm (within the measurement uncertainties) the EIS responsivity
measured directly before the instrument's launch. The measurements also
suggest that the EIS responsivity decreased by a factor of about 1.2
after the first year of operation (although the size of the measurement
uncertainties is comparable to this decrease). The shape of the EIS SW
response curve obtained by EUNIS-07 is consistent with the one measured
in laboratory prior to launch. The absolute value of the quiet-Sun
He II 304 Å intensity measured by EUNIS-07 is consistent with the
radiance measured by CDS NIS in quiet regions near the disk center
and the solar minimum irradiance recently obtained by CDS NIS and the
Solar Dynamics Observatory/Extreme Ultraviolet Variability Experiment.

---------------------------------------------------------
Title: On the Solar Wind Ion Composition Properties With Source
Regions from Low-Latitude and Polar Coronal Holes of Opposite Polarity
Authors: Ko, Y.; Muglach, K.; Wang, Y.; Young, P. R.; Lepri, S. T.;
Laming, J. M.; Popecki, M.
2011AGUFMSH43F..04K Altcode:
During Years 2004-2007 there were frequent appearances of low-latitude
coronal holes (CHs) and low-latitude extension of polar CHs. These
CHs were the source regions of the solar wind measured in-situ at
L1. We find that the ion composition has distinct properties between
solar wind originating from CHs of opposite polarity. Specifically, the
charge states measured by ACE/SWICS were systematically lower-ionized
for solar wind ions from CHs of positive polarity (the 'south CH') than
those of negative polarity (the 'north CH'), regardless of the solar
wind speed. Such differentiation is apparent only in the low-latitude
extension of polar CHs and those non-polar CHs with predicted footpoints
at latitude higher than 15 degrees. Interestingly, earlier work based
on Ulysses fast wind data during the declining/minimum phase of Cycle
22 found that it was the north polar CH that was associated with lower
solar wind charge states, opposite to what we found in the following
solar cycle. We present these results and search for solar properties
that may be factors that govern this north-south difference.

---------------------------------------------------------
Title: Plasma Motions and Heating by Magnetic Reconnection in a 2007
May 19 Flare
Authors: Hara, Hirohisa; Watanabe, Tetsuya; Harra, Louise K.; Culhane,
J. Leonard; Young, Peter R.
2011ApJ...741..107H Altcode:
Based on scanning spectroscopic observations with the Hinode EUV
imaging spectrometer, we have found a loop-top hot source, a fast
jet nearby, and an inflow structure flowing to the hot source that
appeared in the impulsive phase of a long-duration flare at the
disk center on 2007 May 19. The hot source observed in Fe XXIII and
Fe XXIV emission lines has the electron temperature of 12 MK and
density of 1 × 1010 cm-3. It shows excess
line broadening, which exceeds the thermal Doppler width by ~100 km
s-1, with a weak redshift of ~30 km s-1. We have
also observed a blueshifted faint jet whose Doppler velocity exceeds
200 km s-1 with an electron temperature of 9 MK. Coronal
plasmas with electron temperature of 1.2 MK and density of 2.5 ×
109 cm-3 that flow into the loop-top region
with a Doppler velocity of 20 km s-1 have been identified
in the Fe XII observation. They disappeared near the hot source,
possibly by being heated to the hotter faint jet temperature. From
the geometrical relationships of these phenomena, we conclude that
they provide evidence for magnetic reconnection that occurs near the
loop-top region. The estimated reconnection rate is 0.05-0.1, which
supports the Petschek-type magnetic reconnection. Further supporting
evidence for the presence of the slow-mode and fast-mode MHD shocks
in the reconnection geometry is given based on the observed quantities.

---------------------------------------------------------
Title: Forbidden and Intercombination Lines of RR Telescopii:
Wavelength Measurements and Energy Levels
Authors: Young, P. R.; Feldman, U.; Lobel, A.
2011ApJS..196...23Y Altcode: 2011arXiv1102.3101Y
Ultraviolet and visible spectra of the symbiotic nova RR Telescopii
are used to derive reference wavelengths for many forbidden and
intercombination transitions of ions +1 to +6 of elements C, N, O,
Ne, Na, Mg, Al, Si, P, S, Cl, Ar, K, and Ca. The wavelengths are then
used to determine new energy values for the levels within the ions'
ground configurations or first excited configuration. The spectra
were recorded by the Space Telescope Imaging Spectrograph of the
Hubble Space Telescope and the Ultraviolet Echelle Spectrograph of the
European Southern Observatory in 2000 and 1999, respectively, and cover
1140-6915 Å. Particular care was taken to assess the accuracy of the
wavelength scale between the two instruments. An investigation of the
profiles of the emission lines reveals that the nebula consists of at
least two plasma components at different velocities. The components
have different densities, and a simple model of the lines' emissions
demonstrates that most of the lines principally arise from the high
density component. Only these lines were used for the wavelength study.

---------------------------------------------------------
Title: On the ion composition properties in the solar wind from the
north and south polar coronal holes
Authors: Ko, Yuan-Kuen; Muglach, Karin; Wang, Yi-Ming; Young, Peter
R.; Lepri, Susan T.; Laming, J. Martin; Popecki, Mark A.
2011shin.confE.158K Altcode:
During Years 2005-2007 in the declining phase of Cycle 23 there
were frequent appearances of equatorial coronal holes (CHs) and
low-latitude extension of polar CHs that were the source regions of
the solar wind measured in-situ at L1 a few days after these CHs
past the central meridian. We find that the solar wind heavy ions
emanating from the south and north polar CHs have distinct composition
properties. Specifically, the charge states measured by ACE/SWICS
were systematically lower for solar wind ions from the south polar
CHs than those from the north polar CHs, regardless of the solar
wind speed. Interestingly, earlier work based on Ulysses data during
the declining/minimum phase of Cycle 22 found that it was the north
polar CH that was associated with lower solar wind charge states,
opposite to what we found in the following solar cycle. We present
these results and search for solar properties that may be factors
that govern this north-south difference. Implications in solar wind
formation are discussed.

---------------------------------------------------------
Title: Flares Observed By Hinode During 14-18 February 2011
Authors: Young, Peter R.; Doschek, G. A.; Warren, H. P.
2011SPD....42.2213Y Altcode: 2011BAAS..43S.2213Y
Active region AR 11158 produced an X1 flare and several M flares during
2011 February 14-18, and yielded the best set of flare observations
captured by the Hinode satellite in four years. Finding the mechanisms
responsible for flares was one of the major science goals of the Hinode
mission, and data from AR 11158 will be presented to demonstrate how
this goal is being achieved with Hinode data. A particular focus will
be on relating plasma flows and temperature and density changes measured
with the EIS instrument to the magnetic field evolution observed by SOT,
and the coronal evolution observed with SDO/AIA.

---------------------------------------------------------
Title: EUV Spectral Line Formation and the Temperature Structure of
Active Region Fan Loops: Observations with Hinode/EIS and SDO/AIA
Authors: Brooks, David H.; Warren, Harry P.; Young, Peter R.
2011ApJ...730...85B Altcode: 2011arXiv1101.5240B
With the aim of studying active region fan loops using observations
from the Hinode EUV Imaging Spectrometer (EIS) and Solar Dynamics
Observatory Atmospheric Imaging Assembly (AIA), we investigate a number
of inconsistencies in modeling the absolute intensities of Fe VIII
and Si VII lines, and address why spectroheliograms formed from these
lines look very similar despite the fact that ionization equilibrium
calculations suggest that they have significantly different formation
temperatures: log(Te /K) = 5.6 and 5.8, respectively. It is
important to resolve these issues because confidence has been undermined
in their use for differential emission measure (DEM) analysis, and
Fe VIII is the main contributor to the AIA 131 Å channel at low
temperatures. Furthermore, the strong Fe VIII 185.213 Å and Si VII
275.368 Å lines are the best EIS lines to use for velocity studies
in the transition region, and for assigning the correct temperature
to velocity measurements in the fans. We find that the Fe VIII 185.213
Å line is particularly sensitive to the slope of the DEM, leading to
disproportionate changes in its effective formation temperature. If
the DEM has a steep gradient in the log(Te /K) = 5.6-5.8
temperature range, or is strongly peaked, Fe VIII 185.213 Å and Si VII
275.368 Å will be formed at the same temperature. We show that this
effect explains the similarity of these images in the fans. Furthermore,
we show that the most recent ionization balance compilations resolve the
discrepancies in absolute intensities. With these difficulties overcome,
we combine EIS and AIA data to determine the temperature structure of
a number of fan loops and find that they have peak temperatures of
0.8-1.2 MK. The EIS data indicate that the temperature distribution
has a finite (but narrow) width &lt; log (σ_{T_e}/K) = 5.5 which,
in one detailed case, is found to broaden substantially toward the
loop base. AIA and EIS yield similar results on the temperature,
emission measure magnitude, and thermal distribution in the fans,
though sometimes the AIA data suggest a relatively larger thermal
width. The result is that both the Fe VIII 185.213 Å and Si VII
275.368 Å lines are formed at log(Te /K)~ 5.9 in the fans,
and the AIA 131 Å response also shifts to this temperature.

---------------------------------------------------------
Title: Solar plasma spectroscopy: achievements and future challenges
Authors: Del Zanna, Giulio; Tripathi, Durgesh; Young, Peter
2011A&G....52b..17D Altcode:
MEETING REPORT Giulio Del Zanna, Durgesh Tripathi and Peter Young
report on a meeting to celebrate the career of Helen Mason - and the
development of an important field in solar physics.

---------------------------------------------------------
Title: Nurturing The STEM Pipeline: Graduate Student Leadership In
NIRCam's Ongoing E/PO Mission For JWST
Authors: Schlingman, Wayne M.; Stock, N.; Teske, J.; Tyler, K.;
Biller, B.; Donley, J.; Hedden, A.; Knierman, K.; Young, P.
2011AAS...21743101S Altcode: 2011BAAS...4343101S
The Astronomy Camp for Girl Scout Leaders is an education and public
outreach (E/PO) program offered by the science team of the Near-InfraRed
Camera (NIRCam) for NASA's 6.5-meter James Webb Space Telescope
(JWST). Since 2003, astronomy graduate students have helped design
and lead biannual "Train the Trainer” workshops for adults from the
Girl Scouts of the USA (GSUSA), engaging these trainers in the process
of scientific inquiry and equipping them to host astronomy-related
activities at the troop level. These workshops have helped revise the
national GSUSA badge curriculum and directly benefitted thousands
of young girls of all ages, not only in general science and math
education but also in specific astronomical and technological concepts
relating to JWST. To date, nine graduate students have become members
of NIRCam's E/PO team. They have developed curriculum and activities
used to teach concepts in stellar nucleosynthesis, lookback time, galaxy
classification, etc. They have also contributed to the overall strategic
approach and helped lead more general activities in basic astronomy
(night sky, phases of the Moon, the scale of the Solar System and
beyond, stars, galaxies, telescopes, etc.) as well as JWST-specific
research areas in extrasolar planetary systems and cosmology, to
pave the way for girls and women to understand the first images from
JWST. The resulting experience has empowered these students to propose
and to develop their own E/PO programs after graduation as postdocs and
young faculty. They also continue as part of NIRCam's growing worldwide
network of 160 trainers teaching young women essential STEM-related
concepts using astronomy, the night sky environment, applied math,
engineering, and critical thinking. NIRCam and its E/PO program are
funded by NASA under contract NAS5-02105.

---------------------------------------------------------
Title: The Temperature Dependence of Solar Active Region Outflows
Authors: Warren, Harry P.; Ugarte-Urra, Ignacio; Young, Peter R.;
Stenborg, Guillermo
2011ApJ...727...58W Altcode: 2010arXiv1008.2696W
Spectroscopic observations with the EUV Imaging Spectrometer (EIS)
on Hinode have revealed large areas of high-speed outflows at the
periphery of many solar active regions. These outflows are of interest
because they may connect to the heliosphere and contribute to the
solar wind. In this paper, we use slit rasters from EIS in combination
with narrowband slot imaging to study the temperature dependence and
morphology of an outflow region and show that it is more complicated
than previously thought. Outflows are observed primarily in emission
lines from Fe XI to Fe XV. Observations at lower temperatures (Si VII),
in contrast, show bright fan-like structures that are dominated by
inflows. These data also indicate that the morphology of the outflows
and the fans is different, outflows are observed in regions where
there is no emission in Si VII. This suggests that the fans, which
are often associated with outflows in studies involving imaging data,
are not directly related to the active region outflows.

---------------------------------------------------------
Title: Expanding our Knowledge of the Chemical Composition of
Nearby Stars
Authors: Pagano, Michael D.; Young, P.; Butler, P.
2011AAS...21715302P Altcode: 2011BAAS...4315302P
I will be presenting abundances of X elements and physical properties
for a selection of nearby radial velocity planet search candidates. The
abundances are derived from high resolution spectra from MIKE on
Magellan. These are the first results of an attempt to create a
uniform high resolution chemical abundance database that can be used
to understand the chemical evolution of nearby stars, in particular
those with potentially habitable worlds. These high resolution spectra
are the first from a group of 600 nearby stars, obtained by Paul
Butler(Carnigie Institute of Washington).

---------------------------------------------------------
Title: Hinode extreme-ultraviolet imaging spectrometer observations
of a limb active region
Authors: O'Dwyer, B.; Del Zanna, G.; Mason, H. E.; Sterling, A. C.;
Tripathi, D.; Young, P. R.
2011A&A...525A.137O Altcode:
 Aims: We investigate the electron density and temperature
structure of a limb active region. Methods: We have carried out
a study of an active region close to the solar limb using observations
from the Extreme-ultraviolet Imaging Spectrometer (EIS) and the X-ray
telescope (XRT) on board Hinode. The electron density and temperature
distributions of the coronal emission have been determined using
emission line intensity ratios. Differential emission measure (DEM)
analysis and the emission measure (EM) loci technique were used to
examine the thermal structure of the emitting plasma as a function
of distance from the limb. Results: The highest temperature
and electron density values are found to be located in the core of
the active region, with a peak electron number density value of 1.9
× 1010 cm-3 measured using the Fe XII 186.887
Å to 192.394 Å line intensity ratio. The plasma along the line of
sight in the active region was found to be multi-thermal at different
distances from the limb. The EIS and XRT DEM analyses appear to be
in agreement in the temperature interval from log T = 6.5-6.7. 
Conclusions: Our results provide new constraints for models of coronal
heating in active regions.

---------------------------------------------------------
Title: Science Objectives for an X-Ray Microcalorimeter Observing
the Sun
Authors: Laming, J. Martin; Adams, J.; Alexander, D.; Aschwanden, M;
Bailey, C.; Bandler, S.; Bookbinder, J.; Bradshaw, S.; Brickhouse,
N.; Chervenak, J.; Christe, S.; Cirtain, J.; Cranmer, S.; Deiker, S.;
DeLuca, E.; Del Zanna, G.; Dennis, B.; Doschek, G.; Eckart, M.; Fludra,
A.; Finkbeiner, F.; Grigis, P.; Harrison, R.; Ji, L.; Kankelborg,
C.; Kashyap, V.; Kelly, D.; Kelley, R.; Kilbourne, C.; Klimchuk, J.;
Ko, Y. -K.; Landi, E.; Linton, M.; Longcope, D.; Lukin, V.; Mariska,
J.; Martinez-Galarce, D.; Mason, H.; McKenzie, D.; Osten, R.; Peres,
G.; Pevtsov, A.; Porter, K. Phillips F. S.; Rabin, D.; Rakowski, C.;
Raymond, J.; Reale, F.; Reeves, K.; Sadleir, J.; Savin, D.; Schmelz,
J.; Smith, R. K.; Smith, S.; Stern, R.; Sylwester, J.; Tripathi, D.;
Ugarte-Urra, I.; Young, P.; Warren, H.; Wood, B.
2010arXiv1011.4052L Altcode:
We present the science case for a broadband X-ray imager with
high-resolution spectroscopy, including simulations of X-ray spectral
diagnostics of both active regions and solar flares. This is part of
a trilogy of white papers discussing science, instrument (Bandler et
al. 2010), and missions (Bookbinder et al. 2010) to exploit major
advances recently made in transition-edge sensor (TES) detector
technology that enable resolution better than 2 eV in an array that
can handle high count rates. Combined with a modest X-ray mirror, this
instrument would combine arcsecondscale imaging with high-resolution
spectra over a field of view sufficiently large for the study of
active regions and flares, enabling a wide range of studies such as
the detection of microheating in active regions, ion-resolved velocity
flows, and the presence of non-thermal electrons in hot plasmas. It
would also enable more direct comparisons between solar and stellar
soft X-ray spectra, a waveband in which (unusually) we currently have
much better stellar data than we do of the Sun.

---------------------------------------------------------
Title: Evidence for magnetic flux cancelation leading to an ejective
solar eruption observed by Hinode, TRACE, STEREO, and SoHO/MDI
Authors: Sterling, A. C.; Chifor, C.; Mason, H. E.; Moore, R. L.;
Young, P. R.
2010A&A...521A..49S Altcode:
 Aims: We study the onset of a solar eruption involving a
filament ejection on 2007 May 20. Methods: We observe the
filament in Hα images from Hinode/SOT and in EUV with TRACE and
STEREO/SECCHI/EUVI. Hinode/XRT images are used to study the eruption in
soft X-rays. From spectroscopic data taken with Hinode/EIS we obtain
bulk-flow velocities, line profiles, and plasma densities in the
onset region. The magnetic field evolution was observed in SoHO/MDI
magnetograms. Results: We observed a converging motion between
two opposite polarity sunspots that form the primary magnetic polarity
inversion line (PIL), along which resides filament material before
eruption. Positive-flux magnetic elements, perhaps moving magnetic
features (MMFs) flowing from the spot region, appear north of the
spots, and the eruption onset occurs where these features cancel
repeatedly in a negative-polarity region north of the sunspots. An
ejection of material observed in Hα and EUV marks the start of the
filament eruption (its “fast-rise”). The start of the ejection is
accompanied by a sudden brightening across the PIL at the jet's base,
observed in both broad-band images and in EIS. Small-scale transient
brightenings covering a wide temperature range (Log Te =
4.8-6.3) are also observed in the onset region prior to eruption. The
preflare transient brightenings are characterized by sudden, localized
density enhancements (to above Log ne [ cm-3] =
9.75, in Fe XIII) that appear along the PIL during a time when pre-flare
brightenings were occurring. The measured densities in the eruption
onset region outside the times of those enhancements decrease with
temperature. Persistent downflows (red-shifts) and line-broadening
(Fe XII) are present along the PIL. Conclusions: The array of
observations is consistent with the pre-eruption sheared-core magnetic
field being gradually destabilized by evolutionary tether-cutting flux
cancelation that was driven by converging photospheric flows, and the
main filament ejection being triggered by flux cancelation between the
positive flux elements and the surrounding negative field. A definitive
statement however on the eruption's ultimate cause would require
comparison with simulations, or additional detailed observations of
other eruptions occurring in similar magnetic circumstances. The
video that accompanies Fig. 3 is only available in electronic form at
<A href="http://www.aanda.org">http://www.aanda.org</A>

---------------------------------------------------------
Title: Active region moss. Basic physical parameters and their
temporal variation
Authors: Tripathi, D.; Mason, H. E.; Del Zanna, G.; Young, P. R.
2010A&A...518A..42T Altcode: 2010arXiv1005.2220T
Context. Active region moss are transition region phenomena, first noted
in the images recorded by the Transition Region and Coronal Explorer
(TRACE) in λ171. Moss regions are thought to be the footpoints of
hot loops (3-5 MK) seen in the core of active regions. These hot
loops appear “fuzzy” (unresolved). Therefore, it is difficult to
study the physical plasma parameters in individual hot core loops and
hence their heating mechanisms. Moss regions provide an excellent
opportunity to study the physics of hot loops. In addition, they
allow us to study the transition region dynamics in the footpoint
regions. Aims: To derive the physical plasma parameters such as
temperature, electron density, and filling factors in moss regions and
to study their variation over a short (an hour) and a long time period
(5 consecutive days). Methods: Primarily, we have analyzed
spectroscopic observations recorded by the Extreme-ultraviolet Imaging
Spectrometer (EIS) aboard Hinode. In addition we have used supplementary
observations taken from TRACE and the X-Ray Telescope (XRT) aboard
Hinode. Results: The moss emission is strongest in the Fe XII
and Fe XIII lines. Based on analyses using line ratios and emission
measure we found that moss regions have a characteristic temperature
of log T[K] = 6.2. The temperature structure in moss region remains
almost identical from one region to another and it does not change
with time. The electron densities measured at different locations in
the moss regions using Fe XII ratios are about 1-3 × 1010
cm-3 and about 2-4 × 109 cm-3 using
Fe XIII and Fe XIV. The densities in the moss regions are similar in
different places and show very little variation over short and long
time scales. The derived electron density substantially increased (by
a factor of about 3-4 or even more in some cases) when a background
subtraction was performed. The filling factor of the moss plasma
can vary between 0.1-1 and the path length along which the emission
originates is from a few 100 to a few 1000 kms long. By combining the
observations recorded by TRACE, EIS and XRT, we find that the moss
regions correspond to the footpoints of both hot and warm loops.

---------------------------------------------------------
Title: Multiple Component Outflows in an Active Region Observed with
the EUV Imaging Spectrometer on Hinode
Authors: Bryans, P.; Young, P. R.; Doschek, G. A.
2010ApJ...715.1012B Altcode: 2010arXiv1004.5085B
We have used the Extreme Ultraviolet Imaging Spectrometer on the
Hinode spacecraft to observe large areas of outflow near an active
region. These outflows are seen to persist for at least 6 days. The
emission line profiles suggest that the outflow region is composed of
multiple outflowing components, Doppler-shifted with respect to each
other. We have modeled this scenario by imposing a double-Gaussian fit
to the line profiles. These fits represent the profile markedly better
than a single-Gaussian fit for Fe XII and XIII emission lines. For
the fastest outflowing components, we find velocities as high as 200
km s-1. However, there remains a correlation between the
fitted line velocities and widths, suggesting that the outflows are
not fully resolved by the double-Gaussian fit and that the outflow
may be comprised of further components.

---------------------------------------------------------
Title: The Relative Intensity Calibration of Hinode/EIS and SOHO/SUMER
Authors: Landi, E.; Young, P. R.
2010ApJ...714..636L Altcode:
In this work, we have used simultaneous observations of the quiet Sun
above the solar west limb obtained with the Hinode/Extreme ultraviolet
Imaging Spectrograph and SOHO/SUMER instruments to determine their
relative intensity calibration. We used two different methods: intensity
ratios of lines emitted by the same upper level and observed in the
spectral ranges of the two spectrometers, and the determination of
the differential emission measure and total emission measure of the
plasma. We review the uncertainties in our analysis and conclude
that the relative calibration of the two instruments, as it can be
determined from the standard data reduction software of each of them,
is correct within uncertainties.

---------------------------------------------------------
Title: Absolute Radiometric Calibration Of EUNIS, And Calibration
Updates For Hinode/EIS And SOHO/CDS
Authors: Wang, Tongjiang; Thomas, R. J.; Brosius, J. W.; Young, P. R.;
Rabin, D. M.; Davila, J. M.
2010AAS...21640704W Altcode: 2010BAAS...41..860W
The Extreme-Ultraviolet Normal-Incidence Spectrograph sounding rocket
payload was flown in 2006 (EUNIS-06) and 2007 (EUNIS-07), each time
carrying two independent imaging spectrographs covering wave bands
of 300-370 Angstrom in first order and 170-205 Angstrom in second
order. For each flight, the absolute radiometric response of the EUNIS
long-wavelength (LW) channel was directly measured in the same facility
used for pre-flight calibrations of SOHO/CDS and Hinode/EIS. The
wavelength range of the EUNIS LW channel overlaps that of CDS/NIS-1,
and so can provide a direct calibration update for it. The EUNIS-06
observation shows that the efficiency of CDS/NIS-1 has decreased by
a factor about 1.7 compared to that of the previously implemented
calibration. Here we present an update to the absolute calibration for
Hinode/EIS derived with a technique that combines a direct comparison
of line intensities observed in cospatial EUNIS-07 and EIS spectra,
along with density- and temperature-insensitive line intensity ratios.

---------------------------------------------------------
Title: Plasma Flows in Coronal Loops
Authors: Young, Peter R.; Dwyer, B. O.; Mason, H. E.
2010AAS...21630004Y Altcode:
A survey of plasma flows in coronal loops is underway using data from
the Hinode/EIS instrument. The principal target is a study of flows
in 1 MK (so-called 'warm' loops). Using emission lines formed between
logT=5.6 and 6.2 it is possible to study the temperature dependence of
the flows, and also the density of the emitting material. The results
will be critical to making a definitive statement about whether apparent
motions seen in TRACE 171 movies are due to actual mass motion or wave
propagation. In addition we will also comment on the relation between
the flows in warm loops and those in the newly-discovered active region
outflow regions found by Hinode.

---------------------------------------------------------
Title: Elemental Abundance Variations in a Decaying EUV-Bright Region
Authors: Ko, Yuan-Kuen; Landi, E.; Feldman, U.; Young, P.
2010AAS...21640515K Altcode: 2010BAAS...41..891K
The EIS instrument on Hinode observed an EUV-bright region at N15 as it
evolved during a course of four days on December 7-11, 2009. Although
containing no sunspots, this region was associated with a weak magnetic
concentration and exhibited large variations in loop and footpoint
brightening. It was in a decay phase with dispersing magnetic field
and weakening high-temperature emission. We present the variations of
elemental abundances in this region among different spatial structures
and with time. Implications in factors that can be associated with
the First Ionization Potential (FIP) effect will be discussed.

---------------------------------------------------------
Title: New Fe VIII Line Identifications using Observations of the
Quiet Sun
Authors: Landi, E.; Young, P. R.
2010ApJ...713..205L Altcode:
In this work, we study Fe VIII lines emitted in the 1000-1200 Å
wavelength range that originate from levels that also emit transitions
observed in the 190-200 Å wavelength range. The intensity ratios
between such lines depend on atomic physics parameters only and not
on the physical parameters of the emitting plasma: they are excellent
tools to verify the relative intensity calibration of instruments
operating in those wavelength ranges. We first carry out extensive
atomic physics calculations to improve the accuracy of the predicted
intensity ratios of those lines. We then compare the results with
simultaneous Hinode/Extreme Ultraviolet Imaging Spectrometer and
SOHO/SUMER observations of an off-disk quiet-Sun region, identify
four new lines in the 1000-1200 Å range, and discuss their use for
instrument calibration purposes.

---------------------------------------------------------
Title: The Composition of Dwarfs in the Solar Neighborhood
Authors: Pagano, Michael D.; Young, P.; Timmes, F.; Bond, J.
2010AAS...21560503P Altcode: 2010BAAS...36.1129P
We analyze published elemental abundances derived from high-resolution
spectroscopy from radial velocity planet searches. We find that the
sun has anomalous abundances compared to 130 nearby dwarfs. We use a
uniform sample of low mass main sequence stars to reflect differences in
initial composition rather than self-enrichment. We examine individual
[element/Fe] ratios as a function of [Fe/H] for 13 elements. Scenarios
for enrichment of outliers are discussed.

---------------------------------------------------------
Title: Delivery of Supernova Material to the ISM through Ejecta Knots
Authors: Ellinger, C.; Young, P.; Rockefeller, G.; Fryer, C.
2010nuco.confE..29E Altcode: 2010PoS...100E..29E
No abstract at ADS

---------------------------------------------------------
Title: New Flow Diagnostics with EIS
Authors: Young, Peter
2010cosp...38.2923Y Altcode: 2010cosp.meet.2923Y
The EUV Imaging Spectrometer (EIS) on board Hinode obtains high
resolution spectra in the wavelength ranges 170-212 and 246-292
angstroms, giving access to a large number of emission lines from
the solar transition region and corona. Line of sight velocities from
individual spatial pixels (1 arcsec2 )canbemeasuredthroughDopplershif
tstoaprecisionof upto1km/sandanaccuracyof upto5k

---------------------------------------------------------
Title: The effect of 12C + 12C rate
uncertainties on s-process yields
Authors: Bennett, M. E.; Hirschi, R.; Pignatari, M.; Diehl, S.;
Fryer, C.; Herwig, F.; Hungerford, A.; Magkotsios, G.; Rockefeller,
G.; Timmes, F.; Wiescher, M.; Young, P.
2010JPhCS.202a2023B Altcode: 2010arXiv1002.2788B
The slow neutron capture process in massive stars (the weak s-process)
produces most of the s-only isotopes in the mass region 60 &lt;
A &lt; 90. The nuclear reaction rates used in simulations of this
process have a profound effect on the final s-process yields. We
generated 1D stellar models of a 25Modot star varying the
12C + 12C rate by a factor of 10 and calculated
full nucleosynthesis using the post-processing code PPN. Increasing or
decreasing the rate by a factor of 10 affects the convective history
and nucleosynthesis, and consequently the final yields.

---------------------------------------------------------
Title: Characteristics of the Nonthermal Velocity Signature Observed
in the Impulsive Phase of the 2007 May 19 Flare
Authors: Hara, H.; Watanabe, T.; Bone, L. A.; Culhane, J. L.; van
Driel-Gesztelyi, L.; Young, P. R.
2009ASPC..415..459H Altcode:
The Hinode EUV Imaging Spectrometer (EIS) observed a long duration
flare with a weak impulsive phase that appears to conform to the
standard two-ribbon flare reconnection model. EIS scanned the flare
site during the impulsive phase and observed Fe XXIII and Fe XXIV line
emission that closely followed the flare hard X-ray emission while the
line profiles showed significant non-thermal broadening. We suggest
that a shock originating at the reconnection site which sweeps up and
heats the coronal plasma can account for our observations.

---------------------------------------------------------
Title: New Fe IX Line Identifications Using Solar and Heliospheric
Observatory/Solar Ultraviolet Measurement of Emitted Radiation and
Hinode/EIS Joint Observations of the Quiet Sun
Authors: Landi, E.; Young, P. R.
2009ApJ...707.1191L Altcode:
In this work, we study joint observations of Hinode/EUV Imaging
Spectrometer (EIS) and Solar and Heliospheric Observatory/Solar
Ultraviolet Measurement of Emitted Radiation of Fe IX lines emitted
by the same level of the high energy configuration 3s 23p
54p. The intensity ratios of these lines are dependent on
atomic physics parameters only and not on the physical parameters of
the emitting plasma, so that they are excellent tools to verify the
relative intensity calibration of high-resolution spectrometers that
work in the 170-200 Å and 700-850 Å wavelength ranges. We carry out
extensive atomic physics calculations to improve the accuracy of the
predicted intensity ratio, and compare the results with simultaneous
EIS-SUMER observations of an off-disk quiet Sun region. We were
able to identify two ultraviolet lines in the SUMER spectrum that
are emitted by the same level that emits one bright line in the EIS
wavelength range. Comparison between predicted and measured intensity
ratios, wavelengths and energy separation of Fe IX levels confirms the
identifications we make. Blending and calibration uncertainties are
discussed. The results of this work are important for cross-calibrating
EIS and SUMER, as well as future instrumentation.

---------------------------------------------------------
Title: Chianti—An Atomic Database for Emission
Lines. XI. Extreme-Ultraviolet Emission Lines of Fe VII, Fe VIII,
and Fe IX Observed by Hinode/EIS
Authors: Young, P. R.; Landi, E.
2009ApJ...707..173Y Altcode: 2009arXiv0907.3488Y
A detailed study of emission lines from Fe VII, Fe VIII, and Fe
IX observed by the EUV Imaging Spectrometer on board the Hinode
satellite is presented. Spectra in the ranges 170-212 Å and 246-292
Å show strongly enhanced lines from the upper solar transition region
(temperatures 5.4 &lt;= log T &lt;= 5.9) allowing a number of new line
identifications to be made. Comparisons of Fe VII lines with predictions
from a new atomic model reveal new plasma diagnostics, however there
are a number of disagreements between theory and observation for
emission line ratios insensitive to density and temperature, suggesting
improved atomic data are required. Line ratios for Fe VIII also show
discrepancies with theory, with the strong λ185.21 and λ186.60 lines
underestimated by 60%-80% compared to lines between 192 and 198 Å. A
newly identified multiplet between 253.9 and 255.8 Å offers excellent
temperature diagnostic opportunities relative to the lines between 185
and 198 Å, however the atomic model underestimates the strength of
these lines by factors of 3-6. Two new line identifications are made
for Fe IX at wavelengths 176.959 Å and 177.594 Å, while seven other
lines between 186 and 200 Å are suggested to be due to Fe IX but
for which transition identifications cannot be made. The new atomic
data for Fe VII and Fe IX are demonstrated to significantly modify
models for the response function of the Transition Region And Coronal
Explorer 195 Å imaging channel, affecting temperature determinations
from this channel. The data will also affect the response functions
for other solar EUV imaging instruments such as SOHO/EIT, STEREO/EUVI,
and the upcoming AIA instrument on the Solar Dynamics Observatory.

---------------------------------------------------------
Title: CHIANTI—An Atomic Database for Emission Lines. X. Spectral
Atlas of a Cold Feature Observed with Hinode/EUV Imaging Spectrometer
Authors: Landi, E.; Young, P. R.
2009ApJ...706....1L Altcode: 2009arXiv0907.3490L
In this work, we report on a cold, bright portion of an active region
observed by the Hinode/EUV Imaging Spectrometer. The emitting plasma
was very bright at transition region temperatures, and the intensities
of lines of ions formed between 105 and 106
K were enhanced over normal values. The data set constitutes an
excellent laboratory where the emission of transition region ions can
be tested. We first determine the thermal structure of the observed
plasma, and then we use it (1) to develop a spectral atlas, and (2)
to assess the quality of CHIANTI atomic data by comparing predicted
emissivities with observed intensities. We identify several lines
never observed before in solar spectra, and find an overall very good
agreement between CHIANTI-predicted emissivities and observations.

---------------------------------------------------------
Title: Hot Plasma in Nonflaring Active Regions Observed by the
Extreme-Ultraviolet Imaging Spectrometer on Hinode
Authors: Ko, Yuan-Kuen; Doschek, George A.; Warren, Harry P.; Young,
Peter R.
2009ApJ...697.1956K Altcode: 2009arXiv0903.3029K
The Extreme-Ultraviolet Imaging Spectrometer (EIS) on the Hinode
spacecraft obtains high-resolution spectra of the solar atmosphere
in two wavelength ranges: 170-210 and 250-290 Å. These wavelength
regions contain a wealth of emission lines covering temperature regions
from the chromosphere/transition region (e.g., He II, Si VII) up to
flare temperatures (Fe XXIII, Fe XXIV). Of particular interest for
understanding coronal heating is a line of Ca XVII at 192.858 Å,
formed near a temperature of 6 × 106 K. However, this
line is blended with two Fe XI and six O V lines. In this paper we
discuss a specific procedure to extract the Ca XVII line from the
blend. We have performed this procedure on the raster data of five
active regions (ARs) and a limb flare, and demonstrated that the Ca
XVII line can be satisfactorily extracted from the blend if the Ca XVII
flux contributes to at least ~10% of the blend. We show examples of the
high-temperature corona depicted by the Ca XVII emission and find that
the Ca XVII emission has three morphological features in these ARs: (1)
"fat" medium-sized loops confined in a smaller space than the 1 million
degree corona, (2) weaker, diffuse emission surrounding these loops that
spread over the core of the AR, and (3) the locations of the strong Ca
XVII loops are often weak in line emission formed from the 1 million
degree plasma. We find that the emission measure ratio of the 6 million
degree plasma relative to the cooler 1 million degree plasma in the
core of the ARs, using the Ca XVII to Fe XI line intensity ratio as a
proxy, can be as high as 10. Outside of the AR core where the 1 million
degree loops are abundant, the ratio has an upper limit of about 0.5.

---------------------------------------------------------
Title: Temperature Tomography of a Coronal Sigmoid Supporting the
Gradual Formation of a Flux Rope
Authors: Tripathi, Durgesh; Kliem, Bernhard; Mason, Helen E.; Young,
Peter R.; Green, Lucie M.
2009ApJ...698L..27T Altcode: 2009arXiv0904.4782T
Multiwavelength observations of a sigmoidal (S-shaped) solar coronal
source by the EUV Imaging Spectrometer and the X-Ray Telescope
aboard the Hinode spacecraft and by the EUV Imager aboard STEREO are
reported. The data reveal the coexistence of a pair of J-shaped hot
arcs at temperatures T&gt;2 MK with an S-shaped structure at somewhat
lower temperatures (T ≈ 1-1.3 MK). The middle section of the S-shaped
structure runs along the polarity inversion line of the photospheric
field, bridging the gap between the arcs. Flux cancellation occurs
at the same location in the photosphere. The sigmoid forms in the
gradual decay phase of the active region, which does not experience
an eruption. These findings correspond to the expected signatures
of a flux rope forming, or being augmented, gradually by a topology
transformation inside a magnetic arcade. In such a transformation, the
plasma on newly formed helical field lines in the outer flux shell of
the rope (S-shaped in projection) is expected to enter a cooling phase
once the reconnection of their parent field line pairs (double-J shaped
in projection) is complete. Thus, the data support the conjecture that
flux ropes can exist in the corona prior to eruptive activity.

---------------------------------------------------------
Title: Physical Properties In An Equatorial Coronal Hole And Its
Connection To The Solar Wind Properties
Authors: Ko, Yuan-Kuen; Young, P. R.; Lepri, S.; Popecki, M.; Muglach,
K.; Wang, Y.; Laming, J. M.
2009SPD....40.1405K Altcode:
We analyze the physical properties in an equatorial coronal hole
that was observed by Hinode/EIS in two consecutive solar rotations in
February and March of 2009. This coronal hole is the obvious source
region for the solar wind measured in-situ by ACE and STEREO that
exhibits the typical fast-to-slow characteristics in proton speed. We
determine the electron density and temperature structures at several
locations in the coronal hole that may correspond to the footpoints
of the solar wind measured in-situ. We discuss the variations of such
properties between locations as well as between the two rotations. We
compare and discuss such variations in the coronal hole with the
properties in the solar wind, in particular, the ion charge composition.

---------------------------------------------------------
Title: CHIANTI - an atomic database for emission lines. IX. Ionization
rates, recombination rates, ionization equilibria for the elements
hydrogen through zinc and updated atomic data
Authors: Dere, K. P.; Landi, E.; Young, P. R.; Del Zanna, G.; Landini,
M.; Mason, H. E.
2009A&A...498..915D Altcode:
Aims: The goal of the CHIANTI atomic database is to provide a set of
atomic data for the interpretation of astrophysical spectra emitted by
collisionally dominated, high temperature, optically thin sources. Methods: A complete set of ground level ionization and recombination
rate coefficients has been assembled for all atoms and ions of the
elements of H through Zn and inserted into the latest version of the
CHIANTI database, CHIANTI 6. Ionization rate coefficients are taken from
the recent work of Dere (2007, A&amp;A, 466, 771) and recombination
rates from a variety of sources in the literature. These new rate
coefficients have allowed the calculation of a new set of ionization
equilibria and radiative loss rate coefficients. For some ions, such
as Fe VIII and Fe IX, there are significant differences from previous
calculations. In addition, existing atomic parameters have been revised
and new atomic parameters inserted into the database. Results:
For each ion in the CHIANTI database, elemental abundances, ionization
potentials, atomic energy levels, radiative rates, electron and proton
collisional rate coefficients, ionization and recombination rate
coefficients, and collisional ionization equilibrium populations are
provided. In addition, parameters for the calculation of the continuum
due to bremsstrahlung, radiative recombination and two-photon decay are
provided. A suite of programs written in the Interactive Data Language
(IDL) are available to calculate line and continuum emissivities
and other properties. All data and programs are freely available at
http://wwwsolar.nrl.navy.mil/chianti

---------------------------------------------------------
Title: Multiple Component Outflows in Active Regions observed by EIS
Authors: Bryans, Paul; Doschek, G. A.; Young, P. R.
2009SPD....40.1221B Altcode:
We have used the Extreme Ultraviolet Imaging Spectrometer (EIS) on
the Hinode spacecraft to observe large areas of outflow near an active
region. These outflows are seen to persist for a number of days. The
emission line profiles suggest that the outflow region is composed of
multiple outflowing components, Doppler-shifted with respect to each
other. We have modelled this scenario by imposing a double-Gaussian fit
to the line profiles; these fits represent the profile markedly better
than a single Gaussian fit. For the fastest outflowing components,
we find velocities as high as 200 km/s. However, there remains a
correlation between the fitted line velocities and widths, suggesting
that the outflows are not fully resolved by the double-Gaussian fit
and that the outflow may be comprised of further components.

---------------------------------------------------------
Title: CHIANTI Version 6.0 - Inclusion of Ionization and Recombination
Rates
Authors: Dere, Kenneth P.; Landi, E.; Young, P.; Del Zanna, G.; Mason,
H.; Landini, M.
2009SPD....40.1504D Altcode:
A new version of the CHIANTI atomic database for astrophysical
spectroscopy is being prepared for imminent release. This will
constitute Version 6.0. The main focus of this release is the inclusion
of ionization cross-sections and rate coefficients from Dere (2007)
and recombination rate coefficients from the literature, in particular,
the calculations of Badnell and colleagues. A new set of ionization
equilibria have been calculated from these rate coefficients. These
show some significant differences from previous calculations. Atomic
data for many ions have been revised and new calculations are included
that enable the calculation of spectra of ions new to the CHIANTI
database. The radiative loss function has been calculated based on
the CHIANTI Version 6 database for both coronal and photospheric
abundances. A paper describing CHIANTI Version 6.0 in detail has
been accepted for publication in Astronomy and Astrophysics.

---------------------------------------------------------
Title: Improved Atomic Models for EUV Imaging Instruments
Authors: Young, Peter R.; Landi, E.
2009SPD....40.1506Y Altcode:
A combination of new atomic data and new line identifications made
from Hinode/EIS spectra have expanded and improved atomic models for
Fe VII and Fe IX emission lines in the extreme ultraviolet wavelength
range. These have a significant effect on the response functions of
EUV imaging instruments, particularly the 195 angstrom filters used
by SOHO/EIT, TRACE, STEREO/EUVI and SDO/AIA, and will be discussed.

---------------------------------------------------------
Title: Active Region Loops: Hinode/Extreme-Ultraviolet Imaging
Spectrometer Observations
Authors: Tripathi, Durgesh; Mason, Helen E.; Dwivedi, Bhola N.;
del Zanna, Giulio; Young, Peter R.
2009ApJ...694.1256T Altcode: 2009arXiv0901.0095T
We have carried out a study of active region loops using observations
from the Extreme-ultraviolet Imaging Spectrometer (EIS) on board Hinode
using 1” raster data for an active region observed on 2007 May 19. We
find that active region structures which are clearly discernible in
cooler lines (≈1 MK) become "fuzzy" at higher temperatures (≈2
MK). The active region was comprised of redshifted emissions (downflows)
in the core and blueshifted emissions (upflows) at the boundary. The
flow velocities estimated in the two regions located near the footpoints
of coronal loop showed redshifted emission at transition region
temperature and blueshifted emission at coronal temperature. The upflow
speed in these regions increased with temperature. For more detailed
study we selected one particular well-defined loop. Downward flows are
detected along the coronal loop, being stronger in lower-temperature
lines (rising up to 60 km s-1 near the footpoint). The
downflow was localized toward the footpoint in transition region lines
(Si VII) and toward the loop top in high-temperature line (Fe XV). By
carefully accounting for the background emission we found that the
loop structure was close to isothermal for each position along the
loop, with the temperature rising from around 0.8 MK to 1.5 MK from
the close to the base to higher up toward the apex (≈75 Mm). We
derived electron density using well-established line ratio diagnostic
techniques. Electron densities along the active region loop were found
to vary from 1010 cm-3 close to the footpoint to
108.5 cm-3 higher up. A lower electron density,
varying from 109 cm-3 close to the footpoint to
108.5 cm-3 higher up, was found for the lower
temperature density diagnostic. Using these densities we derived filling
factors in along the coronal loop which can be as low as 0.02 near the
base of the loop. The filling factor increased with projected height
of the loop. These results provide important constraints on coronal
loop modeling.

---------------------------------------------------------
Title: Fe XIII Density Diagnostics in the EIS Observing Wavelengths
Authors: Watanabe, T.; Hara, H.; Yamamoto, N.; Kato, D.; Sakaue,
H. A.; Murakami, I.; Kato, T.; Nakamura, N.; Young, P. R.
2009ApJ...692.1294W Altcode:
The diagnostic capability of Fe XIII line features seen in the
170-210 Å waveband of the EUV Imaging Spectrometer (EIS) on Hinode
is investigated, with emphasis on density diagnostics applied to
solar active regions. Four diagnostic line pairs are found to yield
consistent densities ranging from 108.5 to 109.5
cm-3 across an active region using a new theoretical model
of the ion. In separate EIS observations of a small flare, the widely
used line pair, Fe XIII λ203.8/λ202.0, is found to reach the high
density limit predicted by a new theoretical model of the iron ion.

---------------------------------------------------------
Title: High-precision density measurements in the solar
corona. I. Analysis methods and results for Fe XII and Fe XIII
Authors: Young, P. R.; Watanabe, T.; Hara, H.; Mariska, J. T.
2009A&A...495..587Y Altcode: 2008arXiv0805.0958Y
Aims: The EUV Imaging Spectrometer (EIS) instrument on board the Hinode
satellite has access to some of the best coronal density diagnostics,
and the high sensitivity of the instrument now allows electron number
density, N_e, measurements to an unprecedented precision of up to
±5% in active regions. This paper gives a thorough overview of data
analysis issues for the best diagnostics of Fe XII and Fe XIII and
assesses the accuracy of the measurements. Methods: Two density
diagnostics each from Fe XII (λ186.88/λ195.12 and λ196.64/λ195.12)
and Fe XIII (λ196.54/λ202.04 and λ203.82/λ202.04) are analysed in
two active region datasets from 2007 May 3 and 6 that yield densities
in the range 8.5≤ log (N_e/cm-3)≤ 11.0. The densities
are derived using v5.2 of the CHIANTI atomic database. Blending,
line fitting, and instrumental issues are discussed, and line fit
parameters presented. Results: The Fe XII and Fe XIII diagnostics
show broadly the same trend in density across the active region,
consistent with their similar temperatures of formation. However,
the high precision of the EIS measurements demonstrates significant
discrepancies of up to 0.5 dex in derived log Ne values, with
Fe XII always giving higher densities than Fe XIII. The discrepancies
may partly be due to real physical differences between the emitting
regions of the two plasmas, but the dominant factor lies in the
atomic models of the two ions. Two specific problems are identified
for Fe XII λ196.64 and Fe XIII λ203.82: the former is found to
be underestimated in strength by the CHIANTI atomic model, while
the high-density limit of the λ203.82/λ202.04 ratio appears to be
inaccurate in the CHIANTI atomic model. The small grating tilt of the
EIS instrument is found to be very significant when deriving densities
from emission lines separated by more than a few angstroms. Revised
wavelengths of 196.518± 0.003 Å and 196.647± 0.003 Å are suggested
for the Fe XIII λ196.54 and Fe XII λ196.64 lines, respectively.

---------------------------------------------------------
Title: New EUV Fe IX Emission Line Identifications from Hinode/EIS
Authors: Young, P. R.
2009ApJ...691L..77Y Altcode: 2008arXiv0810.5028Y
Four Fe IX transitions in the wavelength range 188-198 Å are identified
for the first time in spectra from the EUV Imaging Spectrometer on
board the Hinode satellite. In particular the emission line at 197.86
Å is unblended and close to the peak of the EIS sensitivity curve,
making it a valuable diagnostic of plasma at around 800,000 K — a
critical temperature for studying the interface between the corona and
transition region. Theoretical ratios among the four lines predicted
from the CHIANTI database reveal weak sensitivity to density and
temperature with observed values consistent with theory. The ratio of
λ197.86 relative to the λ171.07 resonance line of Fe IX is found
to be an excellent temperature diagnostic, independent of density,
and the derived temperature in the analyzed data set is log T = 5.95,
close to the predicted temperature of maximum ionization of Fe IX.

---------------------------------------------------------
Title: On the ultraviolet signatures of small scale heating in
coronal loops
Authors: Parenti, S.; Young, P. R.
2008A&A...492..857P Altcode: 2010arXiv1009.4112P
Aims: Studying the statistical properties of solar ultraviolet emission
lines could provide information about the nature of small scale coronal
heating. We expand on previous work to investigate these properties. We
study whether the predicted statistical distribution of ion emission
line intensities produced by a specified heating function is affected
by the isoelectronic sequence to which the ion belongs, as well
as the characteristic temperature at which it was formed (as found
previously). Particular emphasis is placed on the strong resonance
lines belonging to the lithium isoelectronic sequence. Predictions
for emission lines observed by existing space-based UV spectrometers
are given. The effects on the statistics of a line when observed with
a wide-band imaging instrument rather than a spectrometer are also
investigated. Methods: We use a hydrodynamic model to simulate the
UV emission of a loop system heated by nanoflares on small, spatially
unresolved scales. We select lines emitted at similar temperatures
but belonging to different isoelectronic groups: Fe IX and Ne VIII,
Fe XII and Mg X, Fe XVIII, Fe XIX and Fe XXIV. Results: Our
simulations confirm previous results that almost all lines have an
intensity distribution that follows a power-law, in a similar way
to the heating function. However, only the high temperature lines
best preserve the heating function's power law index (Fe XIX being
the best ion in the case presented here). The Li isoelectronic lines
have different statistical properties with respect to the lines from
other sequences, due to the extended high temperature tail of their
contribution functions. However, this is not the case for Fe XXIV which
may be used as a diagnostic of the coronal heating function. We also
show that the power-law index of the heating function is effectively
preserved when a line is observed by a wide-band imaging instrument
rather than a spectromenter.

---------------------------------------------------------
Title: X-ray energy flow and radiography measurements of evolving
density perturbations
Authors: Moore, A. S.; Graham, P.; Taylor, M. J.; Foster, J. M.;
Sorce, C.; Reighard, A.; MacLaren, S.; Young, P.; Glendinning, G.;
Blue, B. E.; Back, C. A.; Hund, J.
2008APS..DPPPP6113M Altcode:
X-radiation transport through plasma density gradients, such as N-waves,
form a closely coupled system that is challenging to simulate. Such
situations are a key component of the physics of laser-heated
hohlraums occurring in the laser-heated cavity and also in the
laser-entry and any diagnostic holes. In addition the similarity
to some astrophysical conditions may mean that such experiments can
be used as a laboratory-scale analogue for their investigation. To
better understand these phenomena, we present results from a series of
experiments performed at the Omega laser facility. Using a laser-heated
hohlraum drive, a tantalum aerogel with an initial seed perturbation
is heated, and x-rays initially free-stream through the perturbation
before they fill with plasma and radiation transport becomes diffuse. We
present energy flux measurements diagnosed using two different methods,
and complementary radiography results that achieve sufficient contrast,
despite the high background of the hohlraum, to enable the complex shock
interactions and stagnation to be directly observed. These results are
compared with simulations performed using a 2-D Eulerian hydrocode,
which are able to reproduce the overall energetics, and much of the
details of the deceleration shock and axial stagnation region at the
centre of the slit.

---------------------------------------------------------
Title: Magnetic flux cancellation associated with a recurring solar
jet observed with Hinode, RHESSI, and STEREO/EUVI
Authors: Chifor, C.; Isobe, H.; Mason, H. E.; Hannah, I. G.; Young,
P. R.; Del Zanna, G.; Krucker, S.; Ichimoto, K.; Katsukawa, Y.;
Yokoyama, T.
2008A&A...491..279C Altcode:
Aims: We study the physical properties of a recurring solar active
region jet observed in X-rays and extreme-ultraviolet (EUV). Methods: Multi-wavelength data from all three instruments on
board Hinode were analysed. X-ray imaging and spectroscopy of the
microflaring emission associated with the jets was performed with the
Reuven Ramaty High Energy Spectroscopic Imager (RHESSI). Associated
EUV jets were observed with the Sun Earth Connection Coronal and
Heliospheric Investigation (SECCHI)/Extreme Ultraviolet Imager
(EUVI) on board STEREO. Results: We found a correlation between
recurring magnetic flux cancellation close to a pore, the X-ray jet
emission, and associated Ca II H ribbon brightenings. We estimated the
lower limit for the decrease in magnetic energy associated with the
X-ray jet emission at 3 × 1029 erg. The recurring plasma
ejection was observed simultaneously at EUV and X-ray temperatures,
associated with type III radio bursts and microflaring activity at the
jet footpoint. Conclusions: The recurring jet (EUV and X-ray)
emissions can be attributed to chromospheric evaporation flows due to
recurring coronal magnetic reconnection. In this process, the estimated
minimum loss in the magnetic energy is sufficient to account for the
total energy required to launch the jet. Movie of Fig. 3 is only
available in electronic form via http://www.aanda.org

---------------------------------------------------------
Title: Active Region Microflares From Hinode and RHESSI
Authors: Chifor, C.; Hannah, I. G.; Mason, H. E.; Isobe, H.; Yokoyama,
T.; Young, P. R.; Tripathi, D.
2008ASPC..397..164C Altcode:
We are studying microflares (A, B-C class flares) in active regions
using coordinated observations from Hinode and RHESSI. Hinode/EIS
has unprecedented diagnostic power for small, transient activity
in the solar corona, providing temperature, density, and velocity
information. For this purpose, we designed and ran an EIS observing
sequence to provide high-cadence data at both transition region and
coronal temperatures. A preliminary analysis of these observations is
reported, with one data set given as an example.

---------------------------------------------------------
Title: Detection of Waves in the Solar Corona: Kink or Alfvén?
Authors: van Doorsselaere, T.; Nakariakov, V. M.; Verwichte, E.;
Young, P. R.
2008ESPM...12.2.81V Altcode:
Last year, Tomczyk et al. (2007) have conclusively proven that low
amplitude (1km/s) waves are ubiquitously present in the corona. A few
months later, this was followed up with the discovery that chromospheric
spicules carry tremendous wave power (De Pontieu et al., 2007). These
new developments form a basis for coronal seismological magnetic field
mapping of the corona and chromosphere. However, this must be based
upon a confident identification of the observed wave mode. Using
basic MHD wave theory, we demonstrate that the only way to interpret
the observed wave motions is in terms of fast magnetoacoustic kink
waves. We prove that the interpretation in terms of Alfven waves,
as was put forward in the original articles, does not explain the
observed phenomenology, while the fast magnetoacoustic kink waves
reproduce the required observational constraints. To underline the
potential of magnetic field mapping, we discuss a recent observation
of coronal loop kink oscillations observed with Hinode/EIS. Because
of its spectroscopic and imaging capabilities, we are able to measure
the loop density, simultaneously with the loop length. This allows us
to determine the magnetic field with unprecedented accuracy.

---------------------------------------------------------
Title: Density Structure in Active Regions from Hinode/EIS
Authors: Tripathi, D.; Mason, H. E.; Young, P. R.; Chifor, C.; Del
Zanna, G.
2008ASPC..397...45T Altcode:
The Extreme-ultraviolet Imaging Spectrometer (EIS) on board Hinode
provides an excellent opportunity to study the physical plasma
parameters in spatially resolved coronal features. In this paper we
present the density structure in an active region at many different
temperatures. The active region was rastered on May 01, 2007 with the
2^{”} slit. We find that the electron density is highest in the core
of the active region where it exceeds log_{10} N_e = 10.5.

---------------------------------------------------------
Title: Hinode EIS and XRT Observations of Hot Jets in Coronal Holes -
Does the Plasma Escape?
Authors: Baker, D.; van Driel-Gesztelyi, L.; Kamio, S.; Culhane,
J. L.; Harra, L. K.; Sun, J.; Young, P. R.; Matthews, S. A.
2008ASPC..397...23B Altcode:
X-ray jets have been detected in the extreme ultraviolet (EUV) and
soft X-ray observations of Hinode's EIS and XRT instruments. Both
instruments were used to observe the jets in polar and on-disk coronal
holes (CHs). Here, we present a multi-wavelength study of an X-ray
jet and its associated bright point found in an equatorial CH on 19
June 2007. Light curves (LCs) in 22 different emission lines were
compared to that of Hinode/XRT. As we found in a previous study of
two polar X-ray jets, this jet shows a post-jet increase in its EUV
LCs. The post-jet enhancement appears cooler than the jet. We suggest
this feature arises because the hot plasma of the jet, having failed to
reach escape speeds, cools and falls back along the near vertical paths
expected to be created by reconnection with open field lines of CHs. In
addition to the increase in post-jet EUV intensity, we found tentative
evidence of impact heating possibly caused by the fall-back of plasma.

---------------------------------------------------------
Title: Coronal magnetic field measurement using loop oscillations
observed by Hinode/EIS
Authors: Van Doorsselaere, T.; Nakariakov, V. M.; Young, P. R.;
Verwichte, E.
2008A&A...487L..17V Altcode:
We report the first spectroscopic detection of a kink MHD oscillation
of a solar coronal structure by the Extreme-Ultraviolet Imaging
Spectrometer (EIS) on the Japanese Hinode satellite. The detected
oscillation has an amplitude of 1 km s-1 in the Doppler
shift of the FeXII 195 Å spectral line (1.3~MK), and a period of
296~s. The unique combination of EIS's spectroscopic and imaging
abilities enables us to measure simultaneously the mass density and
length of the oscillating loop. This enables us to measure directly
the magnitude of the local magnetic field, the fundamental coronal
plasma parameter, as 39 ± 8~G, with unprecedented accuracy. This
proof of concept makes EIS an exclusive instrument for the full scale
implementation of the MHD coronal seismological technique.

---------------------------------------------------------
Title: Coronal Plasma Motions near Footpoints of Active Region Loops
Revealed from Spectroscopic Observations with Hinode EIS
Authors: Hara, Hirohisa; Watanabe, Tetsuya; Harra, Louise K.; Culhane,
J. Leonard; Young, Peter R.; Mariska, John T.; Doschek, George A.
2008ApJ...678L..67H Altcode:
The solar active region 10938 has been observed from the disk center
to the west limb with the Hinode EUV Imaging Spectrometer. In the
disk-center observation, subsonic upflow motions of tens of km
s-1 and enhanced nonthermal velocities have been found
near the footpoints of the active region loops assuming a single
Gaussian approximation for the emission-line profiles. When the same
part of the active region is observed near the limb, both upflows
and enhanced nonthermal velocities essentially decrease. There
is a strong correlation between Doppler velocity and nonthermal
velocity. Significant deviations from a single Gaussian profile are
found in the blue wing of the line profiles for the upflows. These
suggest that there are unresolved high-speed upflows. We discuss the
implications for coronal heating mechanisms.

---------------------------------------------------------
Title: Outflows at the Edges of Active Regions: Contribution to
Solar Wind Formation?
Authors: Harra, L. K.; Sakao, T.; Mandrini, C. H.; Hara, H.; Imada,
S.; Young, P. R.; van Driel-Gesztelyi, L.; Baker, D.
2008ApJ...676L.147H Altcode:
The formation of the slow solar wind has been debated for many years. In
this Letter we show evidence of persistent outflow at the edges of
an active region as measured by the EUV Imaging Spectrometer on board
Hinode. The Doppler velocity ranged between 20 and 50 km s-1
and was consistent with a steady flow seen in the X-Ray Telescope. The
latter showed steady, pulsing outflowing material and some transverse
motions of the loops. We analyze the magnetic field around the active
region and produce a coronal magnetic field model. We determine from
the latter that the outflow speeds adjusted for line-of-sight effects
can reach over 100 km s-1. We can interpret this outflow as
expansion of loops that lie over the active region, which may either
reconnect with neighboring large-scale loops or are likely to open to
the interplanetary space. This material constitutes at least part of
the slow solar wind.

---------------------------------------------------------
Title: Density structure of an active region and associated moss
using Hinode/EIS
Authors: Tripathi, D.; Mason, H. E.; Young, P. R.; Del Zanna, G.
2008A&A...481L..53T Altcode: 2008arXiv0802.3311T
Context: Studying the problem of active region heating requires precise
measurements of physical plasma parameters such as electron density,
temperature, etc. It is also important to understand the relationship
of coronal structures with the magnetic field. The Extreme-ultraviolet
Imaging Spectrometer (EIS) aboard Hinode provides a rare opportunity to
derive electron density simultaneously at different temperatures. Aims: We study the density structure and characterise plasma in
active regions and associated moss regions. In addition, we study its
relationship to the photospheric magnetic field. Methods: We used
data recorded by the EIS, together with magnetic field measurements
from the Michelson Doppler Imager (MDI) aboard SoHO and images recorded
with the Transition Region And Coronal Explorer (TRACE) and X-Ray
Telescope (XRT/Hinode). Results: We find that the hot core of
the active region is densest with values as high as 1010.5
cm-3. The electron density estimated in specific regions
in the active region moss decreases with increasing temperature. The
moss areas were located primarily on one side of the active region,
and they map the positive polarity regions almost exactly. The density
within the moss region was highest at log T=5.8{-}6.1, with a value
around 1010.0{-10.5} cm-3. The moss densities
were highest in the strong positive magnetic field region. However,
there was no such correlation for the negative polarity areas, where
there was a large sunspot.

---------------------------------------------------------
Title: X-Ray Enabled MOCASSIN: A Three-dimensional Code for
Photoionized Media
Authors: Ercolano, Barbara; Young, Peter R.; Drake, Jeremy J.; Raymond,
John C.
2008ApJS..175..534E Altcode: 2007arXiv0710.2103E
We present a new version of the fully three-dimensional photoionization
and dust radiative transfer code, MOCASSIN, that uses a Monte Carlo
approach for the transfer of radiation. The X-ray enabled MOCASSIN
allows a fully geometry-independent description of low-density gaseous
environments strongly photoionized by a radiation field extending
from radio to gamma rays. The code has been thoroughly benchmarked
against other established codes routinely used in the literature,
using simple plane-parallel models designed to test performance under
standard conditions. We show the results of our benchmarking exercise
and discuss the applicability and limitations of the new code, which
should be of guidance for future astrophysical studies with MOCASSIN.

---------------------------------------------------------
Title: Erratum: "Outflows at the Edges of Active Regions: Contribution
to Solar Wind Formation?" (ApJ, 676, L147 [2008])
Authors: Harra, L. K.; Sakao, T.; Mandrini, C. H.; Hara, H.; Imada,
S.; Young, P. R.; van Driel-Gesztelyi, L.; Baker, D.
2008ApJ...677L.159H Altcode:
No abstract at ADS

---------------------------------------------------------
Title: An active region jet observed with Hinode
Authors: Chifor, C.; Young, P. R.; Isobe, H.; Mason, H. E.; Tripathi,
D.; Hara, H.; Yokoyama, T.
2008A&A...481L..57C Altcode:
Aims:We study the physical properties of an active region (AR) jet in
order to probe the mechanisms responsible for it. Methods: We
report 2007 January 15/16 observations of a recurring jet situated on
the west side of NOAA AR 10938. Multi-wavelength data from all three
instruments onboard Hinode were analysed. This paper focuses on one
instance of a jet observed with the Hinode/EUV Imaging Spectrometer
(EIS). Using EIS raster data we measured the temperatures, Doppler
shifts, density, and filling factor. Results: A strong
blue-shifted component and an indication of a weak red-shifted
component at the base of the jet was observed around Log Te
= 6.2. The up-flow velocities exceeded 150 km s-1. The
jet component was seen over a range of temperatures between 5.4 and
6.4 in Log T_e. Using Fe XII λ186 and λ195 line ratios, we measured
densities above Log Ne = 11 for the high-velocity up-flow
component. We found that the density of the high-velocity up-flow
increases with velocity. We estimate the filling factor in the jet
up-flow to be &lt;0.03. With the Hinode/Solar Optical Telescope (SOT),
we observed recurrent (quasi periodic) magnetic flux cancelations just
before the recurrent jet emission was seen in images taken with the
X-ray Telescope (XRT). Conclusions: The high-velocity up-flows,
together with the density dependence on velocity, support an evaporation
scenario for the acceleration of this jet. The high density and small
filling factor, coupled with the high Doppler velocities are strongly
suggestive of multiple small-scale magnetic reconnection events being
responsible for the production of both EUV and X-ray jets.

---------------------------------------------------------
Title: Spatial Distribution of Nucleosynthesis Products in Cassiopeia
A: Comparison Between Observations and 3D Explosion Models
Authors: Young, P.; Ellinger, C.; Arnett, D.; Fryer, C.; Rockefeller,
G.
2008nuco.confE..20Y Altcode: 2008PoS....53E..20Y; 2008arXiv0811.4655Y
We examine observed heavy element abundances in the Cassiopeia
A supernova remnant as a constraint on the nature of the Cas A
supernova. We compare bulk abundances from 1D and 3D explosion models
and spatial distribution of elements in 3D models with those derived
from X-ray observations. We also examine the cospatial production of
26Al with other species. We find that the most reliable indicator
of the presence of 26Al in unmixed ejecta is a very low S/Si ratio
(~0.05). Production of N in O/S/Si-rich regions is also indicative. The
biologically important element P is produced at its highest abundance
in the same regions. Proxies should be detectable in supernova ejecta
with high spatial resolution multiwavelength observations.

---------------------------------------------------------
Title: Complete nucleosynthesis calculations for low-mass stars
from NuGrid
Authors: Pignatari, M.; Herwig, F.; Bennet, M. E.; Diehl, S.; Fryer,
C. L.; Hirschi, R.; Hungerford, A.; Magkotsios, G.; Rockefeller, G.;
Timmes, F. X.; Young, P.
2008nuco.confE..75P Altcode: 2008PoS....53E..75P; 2008arXiv0811.4658P
Many nucleosynthesis and mixing processes of low-mass stars as they
evolve from the Main Sequence to the thermal-pulse Asymptotic Giant
Branch phase (TP-AGB) are well understood (although of course important
physics components, e.g. rotation, magnetic fields, gravity wave mixing,
remain poorly known). Nevertheless, in the last years presolar grain
measurements with high resolution have presented new puzzling problems
and strong constraints on nucleosynthesis processes in stars. The
goal of the NuGrid collaboration is to present uniform yields for
a large range of masses and metallicities, including low$-$mass
stars and massive stars and their explosions. Here we present
the first calculations of stellar evolution and high-resolution,
post-processing simulations of an AGB star with an initial mass of 2
M_sun and solar-like metallicity (Z=0.01), based on the post-processing
code PPN. In particular, we analyze the formation and evolution of the
radiative 13C-pocket between the 17th TP and the 18th TP. The s-process
nucleosynthesis profile of a sample of heavy isotopes is also discussed,
before the next convective TP occurrence.

---------------------------------------------------------
Title: Nucleosynthesis simulations for a wide range of nuclear
production sites from NuGrid
Authors: Herwig, F.; Diehl, S.; Fryer, C. L.; Hirschi, R.; Hungerford,
A.; Magkotsios, G.; Pignatari, M.; Rockefeller, G.; Timmes, F. X.;
Young, P.; Bennet, M. E.
2008nuco.confE..23H Altcode: 2008PoS....53E..23H; 2008arXiv0811.4653H
Simulations of nucleosynthesis in astrophysical environments are at the
intersection of nuclear physics reaction rate research and astrophysical
applications, for example in the area of galactic chemical evolution or
near-field cosmology. Unfortunately, at present the available yields
for such applications are based on heterogeneous assumptions between
the various contributing nuclear production sites, both in terms of
modeling the thermodynamic environment itself as well as the choice
of specifc nuclear reaction rates and compilations. On the other side,
new nuclear reaction rate determinations are often taking a long time
to be included in astrophysical applications. The NuGrid project
addresses these issues by providing a set of codes and a framework
in which these codes interact. In this contribution we describe the
motivation, goals and first results of the NuGrid project. At the
core is a new and evolving post-processing nuclesoynthesis code (PPN)
that can follow quiescent and explosive nucleosynthesis following
multi-zone 1D-stellar evolution as well as multi-zone hydrodynamic
input, including explosions. First results are available in the areas
of AGB and massive stars.

---------------------------------------------------------
Title: NuGrid: s process in massive stars
Authors: Hirschi, R.; Frischknecht, U.; Pignatari, M.; Thielemann,
F. K.; Bennet, M. E.; Diehl, S.; Fryer, C. L.; Herwig, F.; Hungerford,
A.; Magkotsios, G.; Rockefeller, G.; Timmes, F. X.; Young, P.
2008nuco.confE..83H Altcode: 2008arXiv0811.4654H; 2008PoS....53E..83H
The s-process production in massive stars at very low metallicities
is expected to be negligible due to the low abundance of the neutron
source 22Ne, to primary neutron poisons and decreasing iron seed
abundances. However, recent models of massive stars including the
effects of rotation show that a strong production of 22Ne is possible
in the helium core, as a consequence of the primary nitrogen production
(observed in halo metal poor stars). Using the PPN post-processing code,
we studied the impact of this primary 22Ne on the s process. We find a
large production of s elements between strontium and barium, starting
with the amount of primary 22Ne predicted by stellar models. There
are several key reaction rate uncertainties influencing the s-process
efficiency. Among them, 17O(alpha,gamma) may play a crucial role
strongly influencing the s process efficiency, or it may play a
negligible role, according to the rate used in the calculations. We also
report on the development of a new parallel (MPI) post-processing code
(MPPNP) designed to follow the complete nucleosynthesis in stars on
highly resolved grids. We present here the first post-processing run
from the ZAMS up to the end of helium burning for a 15 solar mass model.

---------------------------------------------------------
Title: Ti44 and Ni56 in core-collapse supernovae
Authors: Magkotsios, G.; Timmes, F. X.; Wiescher, M.; Fryer, C. L.;
Hungerford, A.; Young, P.; Bennet, M. E.; Diehl, S.; Herwig, F.;
Hirschi, R.; Pignatari, M.; Rockefeller, G.
2008nuco.confE.112M Altcode: 2008arXiv0811.4651M; 2008PoS....53E.112M
We investigate the physical conditions where 44Ti and 56Ni are created
in core-collapse supernovae. In this preliminary work we use a series
of post-processing network calculations with parametrized expansion
profiles that are representative of the wide range of temperatures,
densities and electron-to-baryon ratios found in 3D supernova
simulations. Critical flows that affect the final yields of 44Ti and
56Ni are assessed.

---------------------------------------------------------
Title: NuGrid: Nuclear Burning in 3-D Double Degenerate Merger
Simulations
Authors: Diehl, S.; Fryer, C.; Hungerford, A.; Rockefeller, G.;
Bennet, M. E.; Herwig, F.; Hirschi, R.; Pignatari, M.; Magkotsios,
G.; Timmes, F. X.; Young, P.; Clayton, G. C.; Motl, P.; Tohline, J. E.
2008nuco.confE.155D Altcode: 2008PoS....53E.155D
No abstract at ADS

---------------------------------------------------------
Title: Nucleosynthetic Constraints on the Progenitor of Cassiopeia A
Authors: Ellinger, C.; Young, P.; Fryer, C. L.
2008nuco.confE.206E Altcode: 2008PoS....53E.206E
No abstract at ADS

---------------------------------------------------------
Title: Nucleosynthetic Yields from Gamma-Ray Bursts
Authors: Rockefeller, G.; Fryer, C. L.; Young, P.; Bennet, M. E.;
Diehl, S.; Herwig, F.; Hirschi, R.; Hungerford, A.; Pignatari, M.;
Magkotsios, G.; Timmes, F. X.
2008nuco.confE.119R Altcode: 2008PoS....53E.119R
No abstract at ADS

---------------------------------------------------------
Title: Trends in 56Ni and 44Ti Synthesis in Core-Collapse Supernovae
from NuGrid
Authors: Hungerford, A.; Fryer, C. L.; Timmes, F. X.; Young, P.;
Bennet, M. E.; Diehl, S.; Herwig, F.; Hirschi, R.; Pignatari, M.;
Magkotsios, G.; Rockefeller, G.
2008nuco.confE.106H Altcode: 2008PoS....53E.106H
No abstract at ADS

---------------------------------------------------------
Title: FeXIII density diagnostics for solar coronal and flare plasmas
Authors: Watanabe, Tetsuya; Hara, Hirohisa; Yamamoto, Norimasa; Kato,
Takako; Young, Peter R.
2008cosp...37.3434W Altcode: 2008cosp.meet.3434W
Density sensitive FeXIII line ratios were obtained by EUV Imaging
Spectrometer (EUV) on Hinode for quiet-sun, active region, and
flare plasmas. Consistency of density estimates derived from various
density-sensitive line pairs appearing in the EIS observing wavelengths
will be discussed in comparison with theoretical models. The intensity
ratios of FeXIIIλ203.8A/202.0A in flaring active region show its
high-density limit, suggesting that densities at the foot points
of flaring looops exceed 1012 cm-3 , though the value itself is not
exactly consistent with the laboratory data.

---------------------------------------------------------
Title: Coronal Plasma Motions near Footpoints of Active Region Loops
Revealed from Spectroscopic Observations with {it Hinode} EIS
Authors: Hara, Hirohisa; Watanabe, Tetsuya; Harra, Louise K.; Culhane,
J. Leonard; Young, Peter R.; Doschek, G. A.; Mariska, John
2008cosp...37.1175H Altcode: 2008cosp.meet.1175H
We have observed the solar active region 10938 from the disk center
to the west limb with the Hinode EUV Imaging Spectrometer. In the
disk center observation subsonic upflow motions of tens of km s-1 and
enhanced nonthermal velocities have been found near the footpoints of
the active-region loops assuming a single Gaussian approximation for
the emission-line profiles. When the same part of the active region
is observed near the limb, both upflows and enhanced nonthermal
velocities essentially decrease, clearly showing that the enhanced
nonthermal velocities in the disk center observation are mainly due to
line-of-sight motions, which are likely parallel to magnetic field lines
of the coronal loops. There is a strong correlation between Doppler
velocity and nonthermal velocity in the upflow regions. The enhancement
in the blue wing of the line profiles is found for the upflows as a
significant deviation from a single Gaussian profile. These suggest
that there are unresolved high-speed upflows near the footpoints of
active region loops. We discuss the implications for coronal heating
mechanisms.

---------------------------------------------------------
Title: Nucleosynthesis from Supernovae as a Function of Explosion
Energy from NuGrid
Authors: Fryer, C.; Young, P.; Bennet, M. E.; Diehl, S.; Herwig,
F.; Hirschi, R.; Hungerford, A.; Pignatari, M.; Magkotsios, G.;
Rockefeller, G.; Timmes, F. X.
2008nuco.confE.101F Altcode: 2008PoS....53E.101F
No abstract at ADS

---------------------------------------------------------
Title: Solar Transition Region Features Observed with Hinode/EIS
Authors: Young, Peter R.; Del Zanna, Giulio; Mason, Helen E.; Doschek,
George A.; Culhane, Len; Hara, Hirohisa
2007PASJ...59S.727Y Altcode: 2007arXiv0706.1856Y
Two types of solar active region feature prominent at transition region
temperatures are identified in Hinode/EIS data of AR 10938 taken on
2007 January 20. The footpoints of 1 MK TRACE loops are shown to emit
strongly in emission lines formed at log T = 5.4-5.8, allowing the
temperature increase along the footpoints to be clearly seen. A density
diagnostic of Mg VII yields the density in the footpoints, with one
loop showing a decrease from 3 × 109 cm-3 at the
base to 1.5 × 109 cm-3 at a projected height
of 20 Mm. The second feature is a compact active region transition
region brightening which is particularly intense in O V emission
(log T = 5.4) but also has a signature at temperatures up to log T =
6.3. The Mg VII diagnostic gives a density of 4 × 1010
cm-3, and emission lines of Mg VI and Mg VII show line
profiles broadened by 50kms-1 and wings extending beyond
± 200kms-1. Continuum emission in the short wavelength
band is also found to be enhanced, and is suggested to be free-bound
emission from recombination onto He+.

---------------------------------------------------------
Title: Hinode EUV Study of Jets in the Sun's South Polar Corona
Authors: Culhane, Len; Harra, Louise K.; Baker, Deborah; van
Driel-Gesztelyi, Lidia; Sun, Jian; Doschek, George A.; Brooks, David
H.; Lundquist, Loraine L.; Kamio, Suguru; Young, Peter R.; Hansteen,
Viggo H.
2007PASJ...59S.751C Altcode:
A number of coronal bright points and associated plasma jet features
were seen in an observation of the South polar coronal hole during
2007 January. The 40" wide slot was used at the focus of the Hinode
EUV Imaging Spectrometer to provide spectral images for two of these
events. Light curves are plotted for a number of emission lines that
include He II 256Å (0.079MK) and cover the temperature interval from
0.4MK to 5.0MK. Jet speed measurements indicate values less than the
escape velocity. The light curves show a post-jet enhancement in a
number of the cooler coronal lines indicating that after a few minutes
cooling, the plasma fell back to its original acceleration site. This
behavior has not been previously observed by e.g., the Yohkoh Soft
X-ray Telescope due to the comparatively high temperature cut-off
in its response. The observations are consistent with the existing
models that involve magnetic reconnection between emerging flux and the
ambient open field lines in the polar coronal hole. However we do not
have sufficient coverage of lines from lower temperature ion species
to register the Hα-emitting surge material that is associated with
some of these models.

---------------------------------------------------------
Title: Temperature and Density Structures of Solar Corona, A Test
of Iron Line Diagnostic Capability of EIS Instrument on Board Hinode
Authors: Watanabe, Tetsuya; Hara, Hirohisa; Culhane, Len; Harra,
Louise K.; Doschek, George A.; Mariska, John T.; Young, Peter R.
2007PASJ...59S.669W Altcode:
Increased diagnostic capability of the EUV Imaging Spectrometer
(EIS) aboard Hinode (former Solar-B) has been demonstrated with
a set of iron emission lines emerging in the two EIS observing
wavelength bands (170-210Å and 250-290Å) and their line-intensity
ratios. “Abundance-uncertainty” free relative emission measure
distributions as a function of temperature were deduced using only iron
emission lines of various ionization stages. First-light spectra of a
small active region show iron lines ranging from FeVIII (185.2Å and
186.6Å) through FeXVII (204.7Å, 254.9Å, and 269.4Å). Spectra of a
C-class flare confirms the presence of one of these higher temperature
lines (FeXVII at 254.9Å) more clearly, as well showing FeXXIV (192.0Å
and 255.1Å) and FeXXIII (263.8Å), which are normally only seen at
flare temperatures.

---------------------------------------------------------
Title: On-axis Hohlraum Radiography associated with N-Waves in
Stellar Atmospheres.
Authors: Moore, A. S.; Foster, J.; Graham, P.; Taylor, M.; MacLaren,
S.; Young, P.; Glendinning, G.; Reighard, A.; Sorce, C.; Back, C.;
Hund, J.; Blue, B.
2007APS..DPPYO5012M Altcode:
The propagation of weak shocks in a stellar atmosphere, in conjunction
with the high x-ray flux cannot be well-described using weak-shock
theory. Experiments performed at the LLE OMEGA laser attempt to
study shock dynamics similar radiation conditions. Point-projection
radiography was performed along the axis of a 160eV hohlraum,
illuminating the structures formed by the ablation of a 0.2mm
annular slot in a solid Ta disc. Diagnosed whilst laser-driven,
the platform also enables quantitative measurements of x-ray flow
through high-Z foam slot. Backlit images of the radiatively-driven slot
show complex `bubble-like' features at the intersection of ablation
fronts. Despite the 3D aspects of the experiment, 2D simulations,
using the radiation-hydrodynamics code are an excellent qualitative
match to the data, demonstrating that structures result from a high
pressure spike that forms from the colliding ablation fronts driving
a blast wave-like expansion into the dense stagnation region.

---------------------------------------------------------
Title: The Temperature and Density Structure of an Active Region
Observed with the Extreme-Ultraviolet Imaging Spectrometer on Hinode
Authors: Doschek, George A.; Mariska, John T.; Warren, Harry P.;
Culhane, Len; Watanabe, Tetsuya; Young, Peter R.; Mason, Helen E.;
Dere, Kenneth P.
2007PASJ...59S.707D Altcode:
The Extreme-Ultraviolet Imaging Spectrometer (EIS) on Hinode
produces high resolution spectra that can be combined via rasters
into monochromatic images of solar structures, such as active
regions. Electron temperature and density maps of the structures can
be obtained by imaging the structures in different spectral lines with
ratios sensitive to either temperature or density. Doppler maps and
ion temperature maps can be made from spectral line wavelengths and
profiles, respectively. In this paper we discuss coronal temperature
and density distributions within an active region, illustrating the
power of EIS for solar plasma diagnostics.

---------------------------------------------------------
Title: EUV Emission Lines and Diagnostics Observed with Hinode/EIS
Authors: Young, Peter R.; Del Zanna, Giulio; Mason, Helen E.; Dere,
Ken P.; Landi, Enrico; Landini, Massimo; Doschek, George A.; Brown,
Charles M.; Culhane, Len; Harra, Louise K.; Watanabe, Tetsuya; Hara,
Hirohisa
2007PASJ...59S.857Y Altcode: 2007arXiv0706.1857Y
Quiet Sun and active region spectra from the Hinode/EIS instrument are
presented, and the strongest lines from different temperature regions
discussed. A list of emission lines recommended to be included in EIS
observation studies is presented based on analysis of blending and
diagnostic potential using the CHIANTI atomic database. In addition
we identify the most useful density diagnostics from the ions covered
by EIS.

---------------------------------------------------------
Title: Measurements of X-ray energy flow through evolving density
gradients to validate the modeling of stellar atmospheres
Authors: Graham, P.; Foster, J.; Moore, A.; Taylor, M.; MacLaren,
S.; Young, P.; Glendinning, G.; Reighard, A.; Sorce, C.; Back, C.;
Hund, J.; Blue, B.
2007APS..DPPYO5011G Altcode:
Density perturbations, such as N-waves, in stellar atmospheres
are coupled to the X-ray radiation field and so their evolution is
challenging to simulate [1]. To assess current modeling capabilities
an analogous problem was generated on the LLE OMEGA laser using a
hohlraum to drive X-rays through tantalum aerogel with an initial seed
perturbation. X-rays diffuse preferentially through the lower density
material and the flow changes over time as the heated mass evolves. The
energy flow was diagnosed using two methods, direct flux and hohlraum
calorimetry, which are compared to assess the best technique. In both
cases multiple flux diagnostics on different lines of sight were used,
including photodiode and photoconductive detectors, to crosscheck
results. In addition, 2D framing images of X-ray emission were taken
to correlate with the flux measurements. The suite of data will be
presented and compared against modeling. [1] Mihalas &amp; Mihalas,
`Foundations of Radiation Hydrodynamics', Dover (1999).

---------------------------------------------------------
Title: Coronal Dimming Observed with Hinode: Outflows Related to a
Coronal Mass Ejection
Authors: Harra, Louise K.; Hara, Hirohisa; Imada, Shinsuke; Young,
Peter R.; Williams, David R.; Sterling, Alphonse C.; Korendyke,
Clarence; Attrill, Gemma D. R.
2007PASJ...59S.801H Altcode:
Coronal dimming has been a signature used to determine the source
of plasma that forms part of a coronal mass ejection (CME) for many
years. Generally dimming is detected through imaging instruments such
as SOHO EIT by taking difference images. Hinode tracked active region
10930 from which there were a series of flares. We combined dimming
observations from EIT with Hinode data to show the impact of flares
and coronal mass ejections on the region surrounding the flaring
active region, and we discuss evidence that the eruption resulted in
a prolonged steady outflow of material from the corona. The dimming
region shows clear structure with extended loops whose footpoints are
the source of the strongest outflow (≈ 40 kms-1). This
confirms that the loops that are disrupted during the event do lose
plasma and hence are likely to form part of the CME. This is the
first time the velocity of the coronal plasma has been measured in an
extended dimming region away from the flare core. In addition there
was a weaker steady outflow from extended, faint loops outside the
active region before the eruption, which is also long lasting. These
were disturbed and the velocity increased following the flare. Such
outflows could be the source of the slow solar wind.

---------------------------------------------------------
Title: Application of CHIANTI to Solar-B
Authors: Dere, K.; Landi, E.; Del Zanna, G.; Young, P.; Mason, H.;
Landini, M.
2007ASPC..369...35D Altcode:
CHIANTI (http://wwwsolar.nrl.navy.mil/chianti.html) has been developed
to support the interpretation of solar and astrophysical spectroscopic
measurements. The most recent release, version 5.0 (Landi et al. 2005)
presents an improvement over previous versions by including new
large scale datasets for Fe ions from Fe XVII to Fe XXIV for X-ray
emission and improved atomic data for EUV line emission. We will
demonstrate how this can be applied to the analysis of XRT and EIS
data, in particular. For example, new excitation rates for Fe XII have
resolved a long standing problem in the use of Fe XII line ratios as
accurate density diagnostics. Current work involves improvements to
ionization and recombination rates which will also be useful in the
interpretation of Solar-B data

---------------------------------------------------------
Title: Studying Transition Region Phenomena with Solar-B/EIS
Authors: Young, P.
2007ASPC..369..307Y Altcode: 2007arXiv0708.1672Y
Transition region lines in active regions can become strongly enhanced
in coronal footpoints and active region blinkers. The weak transition
region lines found in the Solar-B/EIS wavebands will thus become useful
for diagnostic studies of these events. EIS count rates predicted
from SOHO/CDS spectra are presented, and a Mg VII density diagnostic
is highlighted.

---------------------------------------------------------
Title: Nonthermal Velocities in Solar Active Regions Observed with
the Extreme-Ultraviolet Imaging Spectrometer on Hinode
Authors: Doschek, G. A.; Mariska, J. T.; Warren, H. P.; Brown, C. M.;
Culhane, J. L.; Hara, H.; Watanabe, T.; Young, P. R.; Mason, H. E.
2007ApJ...667L.109D Altcode:
We discuss nonthermal velocities in an active region as revealed
by the Extreme-Ultraviolet Imaging Spectrometer (EIS) on the Hinode
spacecraft. The velocities are derived from spectral line profiles in
the extreme-ultraviolet (EUV) from a strong line of Fe XII at 195.12 Å
by fitting each line profile to a Gaussian function. We compare maps
of the full width at half-maximum values, the Fe XII spectral line
intensity, the Fe XII Doppler shift, the electron temperature, and
electron density. We find that the largest widths in the active region
do not occur in the most intense regions, but seem to concentrate in
less intense regions, some of which are directly adjacent to coronal
loops, and some of which concentrate in regions which also exhibit
relative Doppler outflows. The increased widths can also occur over
extended parts of the active region.

---------------------------------------------------------
Title: The EUV Imaging Spectrometer for Hinode
Authors: Culhane, J. L.; Harra, L. K.; James, A. M.; Al-Janabi, K.;
Bradley, L. J.; Chaudry, R. A.; Rees, K.; Tandy, J. A.; Thomas, P.;
Whillock, M. C. R.; Winter, B.; Doschek, G. A.; Korendyke, C. M.;
Brown, C. M.; Myers, S.; Mariska, J.; Seely, J.; Lang, J.; Kent,
B. J.; Shaughnessy, B. M.; Young, P. R.; Simnett, G. M.; Castelli,
C. M.; Mahmoud, S.; Mapson-Menard, H.; Probyn, B. J.; Thomas, R. J.;
Davila, J.; Dere, K.; Windt, D.; Shea, J.; Hagood, R.; Moye, R.; Hara,
H.; Watanabe, T.; Matsuzaki, K.; Kosugi, T.; Hansteen, V.; Wikstol, Ø.
2007SoPh..243...19C Altcode:
The EUV Imaging Spectrometer (EIS) on Hinode will observe solar corona
and upper transition region emission lines in the wavelength ranges
170 - 210 Å and 250 - 290 Å. The line centroid positions and profile
widths will allow plasma velocities and turbulent or non-thermal line
broadenings to be measured. We will derive local plasma temperatures and
densities from the line intensities. The spectra will allow accurate
determination of differential emission measure and element abundances
within a variety of corona and transition region structures. These
powerful spectroscopic diagnostics will allow identification
and characterization of magnetic reconnection and wave propagation
processes in the upper solar atmosphere. We will also directly study
the detailed evolution and heating of coronal loops. The EIS instrument
incorporates a unique two element, normal incidence design. The optics
are coated with optimized multilayer coatings. We have selected highly
efficient, backside-illuminated, thinned CCDs. These design features
result in an instrument that has significantly greater effective area
than previous orbiting EUV spectrographs with typical active region
2 - 5 s exposure times in the brightest lines. EIS can scan a field
of 6×8.5 arc min with spatial and velocity scales of 1 arc sec and
25 km s−1 per pixel. The instrument design, its absolute
calibration, and performance are described in detail in this paper. EIS
will be used along with the Solar Optical Telescope (SOT) and the X-ray
Telescope (XRT) for a wide range of studies of the solar atmosphere.

---------------------------------------------------------
Title: Coronal dimming observed with Hinode
Authors: Harra, Louise; Hara, H.; Young, P.; Williams, D.; Sterling,
A.; Attrill, G.
2007AAS...210.6305H Altcode: 2007BAAS...39..172H
Coronal dimming has been a technique used to determine the source
of plasma that forms part of a coronal mass ejection. Generally
dimming is detected through imaging instruments such as SOHO EIT by
taking difference images. In a few cases the SOHO-CDS has been used
to determine outflowing material, and a decrease in density. Hinode
tracked active region 10930 from which there were a series of flares. We
combine dimming observations from EIT with Hinode data to show the
impact of flares and coronal mass ejections on the region surrounding
the flaring active region, and we discuss evidence that the eruption
resulted in a prolonged steady outflow of material from the corona.

---------------------------------------------------------
Title: Hinode EIS Observations of Solar Active Regions
Authors: Mariska, John T.; Doschek, G. A.; Warren, H. P.; Brooks,
D. H.; Young, P. R.; Watanabe, T.; Culhane, J. L.
2007AAS...210.7202M Altcode: 2007BAAS...39R.178M
The EUV Imaging Spectrometer (EIS) on the Hinode satellite provides
high spatial and spectral resolution data along a 512 arcsec slit in
two wavelength ranges, 170--210 Angstroms and 250--290 Angstroms. These
wavelengths mostly contain emission lines from upper transition region
and coronal plasmas. Emission from these wavelengths is routinely
imaged using instruments such as the EIT on SOHO and TRACE, but there
are few high-resolution spectra to aid in more deeply understanding
the physical conditions and dynamics associated with the intensity
variations seen in the images. In this presentation, we show some
initial results from EIS active region studies aimed at mapping the
density, temperature, nonthermal broadening, and Doppler shifts in
active regions. This presentation focusses on spectroheliograms of
active regions in diagnostically interesting spectral lines. These
show the overall active region morphology and the behavior of Doppler
shifts, nonthermal velocities, and densities as a function of position,
but at the expense of high time resolution. Other presentations will
focus on how the observed physical parameters vary with time.

---------------------------------------------------------
Title: Multi-wavelength Analysis of a Quiet Solar Region
Authors: Tsiropoula, G.; Tziotziou, K.; Giannikakis, J.; Young, P.;
Schühle, U.; Heinzel, P.
2007ASPC..368..171T Altcode: 2007arXiv0704.1592T
We present observations of a solar quiet region obtained by the
ground-based Dutch Open Telescope (DOT), and by instruments on the
spacecraft SOHO and TRACE. The observations were obtained during a
coordinated observing campaign on October 2005. The aim of this work
is to present the rich diversity of fine-scale structures that are
found at the network boundaries and their appearance in different
instruments and different spectral lines that span the photosphere
to the corona. Detailed studies of these structures are crucial to
understanding their dynamics in different solar layers, as well as
the role such structures play in the mass balance and heating of the
solar atmosphere.

---------------------------------------------------------
Title: Iron Line Ratio Analysis in an Active Region
Authors: Watanabe, Tetsuya; Hara, H.; Culhane, J. L.; Harra, L. K.;
Doschek, G. A.; Mariska, J. T.; Young, P. R.; Hinode EIS Team
2007AAS...210.7204W Altcode: 2007BAAS...39..179W
Increased diagnostic capability of the EIS instrument on board Hinode
(Solar-B) is demonstrated with a set of iron emission lines appearing
in the two EIS observing wavelengths (170 - 210 A &amp; 250 - 290
A) and their line intensity ratios. First-light spectra of a small
active region show iron lines at the ionization stages of FeVIII
(185.2 A &amp; 186.6 A) through FeXVII (204.7 A, 254.9 A, &amp; 269.4
A). Decay phase spectra of a C-class flare confirms the presence of
this higher temperature line; FeXVII at 254.9 A more clearly, as well
as those lines of flare temperatures; FeXXIV (192.0 A &amp; 255.1 A)
and FeXXIII (263.8 A).

---------------------------------------------------------
Title: Initial Results On Active Region Loop Morphology From Hinode
EIS And XRT.
Authors: Brooks, David; Warren, H.; Young, P.; Matsuzaki, K.;
Williams, D.
2007AAS...210.6307B Altcode: 2007BAAS...39Q.172B
Theoretically, magnetic fields are expected to expand as they rise
above the photosphere and into the corona, so the apparent uniform
cross-sections of active region coronal loops are difficult to
understand. There has been some debate in the community as to whether
coronal loops really have constant cross-sections (as suggested by
TRACE and SXT), or are actually unresolved and composed of expanding
threads within the constant cross-section envelopes. Furthermore,
loop expansion is critical to the success or failure of hydrostatic
models in reproducing the observed intensities and morphology in
active region loops, bright points, and the full Sun. Hinode EIS and
XRT provide unprecedented spatial resolution at high temperatures
that can be used to reexamine the morphology of active region loops
and provide new insights. Here we present initial results from our
study of active region loop widths with EIS and XRT.

---------------------------------------------------------
Title: Science With The Extreme Ultraviolet Spectrometer For Solar
Orbiter
Authors: Young, P. R.; EUS Science Working Group
2007ESASP.641E..21Y Altcode:
The CCLRC Rutherford Appleton Laboratory (UK) is leading a consortium
that proposes to build an ultraviolet spectrometer for Solar Orbiter
provisionally called the Extreme Ultraviolet Spectrometer (EUS). The
selection of wavelength bands for EUS has been re-assessed by the EUS
Science Working Group in recent months and the final decision calls for
three wavelength bands covering 700-800 Å, 970-1040 Å, and 1163-1265
Å. The key features of these bands are summarised here, and particular
science topics that can be addressed by EUS are discussed.

---------------------------------------------------------
Title: Optical Design Of The Extreme Ultraviolet Spectrometer (EUS)
On Board Solar Orbiter
Authors: Middleton, K.; Da Deppo, V.; Poletto, L.; Schühle, U.;
Thomas, R. J.; Young, P. R.
2007ESASP.641E..48M Altcode:
We present optical designs for the Extreme Ultraviolet Imaging
Spectrometer (EUS) proposed for Solar Orbiter. We summarise the
scientific requirements for EUS and show how they translate into an
instrument specification and optical design. Two design options are
presented: one utilising a normal incidence telescope and one utilising
a grazing incidence telescope. Both options use the same design of
spectrometer, which incorporates a Toroidal Varied Line-Space (TVLS)
grating, allowing high quality imaging at relatively large spectrometer
magnifications. This results in a very compact yet high performance
design. We give estimates of the instrument's optical performance and
throughput and discuss briefly some heat management strategies.

---------------------------------------------------------
Title: MARS Valley Networks Project: Martian Valley Network Analysis
Run-off or Sapping? - A WebGIS approach
Authors: Luo, W.; Kitts, K. B.; Young, P.; Schwantes, F. W.; Hung, W.
2006AGUFMED42A..07L Altcode:
We report the progress made in a two-year NASA funded EPO project,
which takes advantage of the latest WebGIS technology to bring real
NASA data to high school classrooms. The only requirement for the
WebGIS is an Internet connection and a standard web browser allowing
the widest possible accessibility. The overall goal of the project is
to enhance the students' interest in science and to directly engage
them in the actual process of conducting scientific research with a
real scientific research question and real scientific datasets. The
students will be exposed to the full process of conducting real
scientific investigation: collecting evidence, analyzing data,
formulating alternative hypotheses, and communicating and debating
with their peers about their findings. Such opportunities are rarely
available in the middle through high school level. We have set up the
WebGIS (http://marsproject.niu.edu) and have completed the student
and teacher tutorials. The standard-based student modules are being
finalized and tested by two Master teachers this semester. A training
workshop for teachers will be held Spring 2007. Approximately twenty
classrooms will be participating fully by the 2007-08 school year.

---------------------------------------------------------
Title: Solar And Cosmic Ray Physics And The Space Environment:
Studies For And With LISA
Authors: Shaul, D. N. A.; Aplin, K. L.; Araújo, H.; Bingham, R.;
Blake, J. B.; Branduardi-Raymont, G.; Buchman, S.; Fazakerley, A.;
Finn, L. S.; Fletcher, L.; Glover, A.; Grimani, C.; Hapgood, M.;
Kellet, B.; Matthews, S.; Mulligan, T.; Ni, W. -T.; Nieminen, P.;
Posner, A.; Quenby, J. J.; Roming, P.; Spence, H.; Sumner, T.; Vocca,
H.; Wass, P.; Young, P.
2006AIPC..873..172S Altcode:
With data analysis preparations for LISA underway, there has been
renewed interest in studying solar, cosmic ray and environmental
physics for, and using LISA. The motivation for these studies is two
fold. The primary incentive is to predict and consequently minimize
the impact of disturbances associated with these factors, to maximize
LISA's gravitational wave scientific yield. The second stimulus is
the unique opportunity that is afforded by LISA's long-baseline
3-spacecraft configuration for studies of solar, cosmic ray and
environmental physics. Here we present an overview of recent progress
in these studies.

---------------------------------------------------------
Title: High-Ionization Forbidden Lines in the UV Spectrum of AG
Draconis
Authors: Young, P. R.; Dupree, A. K.; Espey, B. R.; Kenyon, S. J.
2006ApJ...650.1091Y Altcode:
High-ionization forbidden lines from Ca VII, Fe VII, Mg V, Mg VI,
Mg VII, and Si VII are found in recent Hubble Space Telescope STIS
ultraviolet spectra of the symbiotic star AG Draconis. These species
have ionization potentials between 99 and 205 eV, which are unexpected
due to the high density (~1010 cm-3) of the
AG Dra nebula. The identification of the Mg VII λλ2510, 2629 lines
is the first in astrophysical or laboratory spectra, and revised rest
wavelengths are suggested from the STIS spectra. Plasma diagnostics from
Mg V-VII are applied, but do not provide a consistent constraint on
temperature or density. A density &gt;=108 cm-3
is confirmed, however. The lines show double-peaked profiles with
widths ~100-160 km s-1, suggestive of an origin in an
accretion disk. However, the line widths, if identified with motion
in a Keplerian disk, indicate radii much smaller than sizes inferred
from the line fluxes themselves. The source of these high-ionization
forbidden lines remains unidentified.

---------------------------------------------------------
Title: Multi-Wavelength Investigation of a Sigmoidal Active Region
Authors: Tripathi, D.; Mason, H. E.; Young, P. R.
2006ESASP.617E.148T Altcode: 2006soho...17E.148T
No abstract at ADS

---------------------------------------------------------
Title: Java Message Service (JMS) use in the Telescope Automation
and Remote Observing System (TAROS)
Authors: Czezowski, A.; Green, A.; Hovey, G.; Jarnyk, M.; Nielsen, J.;
Roberts, B.; Sebo, K.; Smith, D.; Vaccarella, A.; Wilson, G.; Young, P.
2006ASPC..351..208C Altcode: 2006adass..15..208C
JMS is an enterprise messaging system, part of the Java 2 Platform,
Enterprise Edition (J2EE). It provides distributed applications a method
for asynchronously sending and receiveing critical data and events. It
also decouples the message delivery management subsystem from the
application itself. TAROS is a distributed system that will allow the
Australian National University telescopes at Siding Spring Observatory
to be operated automatically or interactively over the Internet. JMS
technology is used throughout TAROS, providing a communication path
between the TAROS back-end software components as well as between
TAROS and its external clients.

---------------------------------------------------------
Title: The Solar Neon Abundance and the Standard Solar Model
Authors: Young, P. R.
2006ESASP.617E..47Y Altcode: 2006soho...17E..47Y
No abstract at ADS

---------------------------------------------------------
Title: CHIANTI-An Atomic Database for Emission Lines. VII. New Data
for X-Rays and Other Improvements
Authors: Landi, E.; Del Zanna, G.; Young, P. R.; Dere, K. P.; Mason,
H. E.; Landini, M.
2006ApJS..162..261L Altcode:
The CHIANTI atomic database contains atomic energy levels, wavelengths,
radiative transition probabilities, and collisional excitation data for
a large number of ions of astrophysical interest. CHIANTI also includes
a suite of IDL routines to calculate synthetic spectra and carry out
plasma diagnostics. Version 5 has been released, which includes several
new features, as well as new data for many ions. The new features in
CHIANTI are as follows: the inclusion of ionization and recombination
rates to individual excited levels as a means to populate atomic
levels; data for Kα and Kβ emission from Fe II to Fe XXIV; new data
for high-energy configurations in Fe XVII to Fe XXIII; and a complete
reassessment of level energies and line identifications in the X-ray
range, multitemperature particle distributions, and photoexcitation
from any user-defined radiation field. New data for ions already in
the database, as well as data for ions not present in earlier versions
of the database, are also included. Version 5 of CHIANTI represents a
major improvement in the calculation of line emissivities and synthetic
spectra in the X-ray range and expands and improves theoretical spectra
calculations in all other wavelength ranges.

---------------------------------------------------------
Title: The Ne/O abundance ratio in the quiet Sun
Authors: Young, P. R.
2005A&A...444L..45Y Altcode: 2005astro.ph.10264Y
Context: . Aims: .To determine the neon-to-oxygen abundance in the
quiet Sun, a proxy for the photospheric abundance ratio. Methods:
.An emission measure method applied to extreme ultraviolet emission
lines of Ne iv-vi and O iii-v ions observed by the Coronal Diagnostic
Spectrometer on the SOHO satellite. Results: .The average Ne/O
abundance ratio in supergranule cell centre regions is 0.18± 0.05,
while in supergranule network regions is 0.16± 0.04. A photospheric
Ne/O ratio of 0.17± 0.05 is suggested, in good agreement with the most
recent compilation of solar photospheric abundances, but discrepant with
a recent Ne/O ratio derived from stellar X-ray spectra and revised neon
abundances suggested from solar interior models. Conclusions: .

---------------------------------------------------------
Title: Telescope Automation and Remote Observing System (TAROS)
Authors: Wilson, G.; Czezowski, A.; Hovey, G. R.; Jarnyk, M. A.;
Nielsen, J.; Roberts, B.; Sebo, K.; Smith, D.; Vaccarella, A.;
Young, P.
2005ASPC..347..563W Altcode: 2005adass..14..563W
TAROS is a system that will allow for the Australian National University
telescopes at a remote location to be operated automatically or
interactively with authenticated control via the internet. TAROS is
operated by a Java front-end GUI and employs the use of several Java
technologies - such as Java Message Service (JMS) for communication
between the telescope and the remote observer, Java Native Interface to
integrate existing data acquisition software written in C++ (CICADA)
with new Java programs and the JSky collection of Java GUI components
for parts of the remote observer client. In this poster the design
and implementation of TAROS is described.

---------------------------------------------------------
Title: The element abundance FIP effect in the quiet Sun
Authors: Young, P. R.
2005A&A...439..361Y Altcode: 2005astro.ph..3038Y
The Mg/Ne abundance ratio in the quiet Sun is measured in both
network and supergranule cell centre regions through EUV spectra
from the Coronal Diagnostic Spectrometer on SOHO. Twenty four sets
of data over the period 1996 March to 1998 June (corresponding to
solar minimum and the onset of the next cycle) are studied. Emission
lines of the sequences Ne IV-VII and Mg V-VIII are simultaneously
analysed by comparing with theoretical emissivities from the CHIANTI
database to yield the Mg/Ne abundance and emission measure over the
temperature region 5.0≤log T≤ 6.1. The average enhancements over the
photospheric Mg/Ne abundance are found to be 1.25± 0.10 (network) and
1.66± 0.23 (cell centres), implying that the structures making up the
transition region have close-to photospheric abundances. In particular,
this implies that only a small fraction of the quiet Sun can connect to
the solar wind where the Mg/Ne abundance ratio is found to be factors
4-5 greater than the photospheric value. The quiet Sun spectra are also
utilised to determine the coronal density and temperature, leading to
average values of 2.6+0.5-0.4× 108
cm-3 and log (T/K)=5.95± 0.02. No significant trend with the
rise in solar activity during 1996-98 is found for any of the derived
quantities, implying that quiet Sun regions show little dependence on
the solar cycle.

---------------------------------------------------------
Title: Recent developments of the CHIANTI database in the X-ray
wavelength range
Authors: Landi, E.; Dere, K. P.; Young, P. R.; del Zanna, G.; Mason,
H. E.; Landini, M.
2005AIPC..774..409L Altcode:
CHIANTI is a database of atomic data and transition probabilities that
allows the calculation of synthetic spectra and plasma diagnostics of
optically thin plasmas. It is primarily suited for wavelengths shorter
than 2000 Å but in principle can also be used at longer wavelengths. In
the present paper we illustrate the latest development of the CHIANTI
database, that include a huge expansion of the database in the X-ray
wavelength range, the renewal of several data in the EUV range, and
the inclusion of ionization and recombination in the level population
calculation. This enhanced database will constitute the Version 5
of CHIANTI.

---------------------------------------------------------
Title: A Far-Ultraviolet Spectroscopic Survey of Luminous Cool Stars
Authors: Dupree, A. K.; Lobel, A.; Young, P. R.; Ake, T. B.; Linsky,
J. L.; Redfield, S.
2005ApJ...622..629D Altcode: 2004astro.ph.12539D
The Far Ultraviolet Spectroscopic Explorer (FUSE) ultraviolet spectra
of eight giant and supergiant stars reveal that high-temperature
(3×105 K) atmospheres are common in luminous cool stars
and extend across the color-magnitude diagram from α Car (F0 II)
to the cool giant α Tau (K5 III). Emission present in these spectra
includes chromospheric H Lyβ, Fe II, C I, and transition region lines
of C III, O VI, Si III, and Si IV. Emission lines of Fe XVIII and Fe
XIX signaling temperatures of ~107 K and coronal material
are found in the most active stars, β Cet and 31 Com. A short-term
flux variation, perhaps a flare, was detected in β Cet during our
observation. Stellar surface fluxes of the emission of C III and
O VI are correlated and decrease rapidly toward the cooler stars,
reminiscent of the decay of magnetically heated atmospheres. Profiles
of the C III λ977 lines suggest that mass outflow is underway at
T~80,000 K and the winds are warm. Indications of outflow at higher
temperatures (3×105 K) are revealed by O VI asymmetries and
the line widths themselves. High-temperature species are absent in the
M supergiant α Ori. Narrow fluorescent lines of Fe II appear in the
spectra of many giants and supergiants, apparently pumped by H Lyα,
and formed in extended atmospheres. Instrumental characteristics that
affect cool star spectra are discussed.

---------------------------------------------------------
Title: Fe VII lines in the spectrum of RR Telescopii
Authors: Young, P. R.; Berrington, K. A.; Lobel, A.
2005A&A...432..665Y Altcode: 2004astro.ph.12157Y
Thirteen transitions within the ground 3d2 configuration
of Fe vii are identified in ultraviolet and optical spectra of
the symbiotic star RR Telescopii obtained with the STIS instrument
of the Hubble Space Telescope. The line fluxes are compared with
theoretical data computed with the recent atomic data of Berrington
et al., and high resolution optical spectra from VLT/UVES are
used to identify blends. Seven branching ratios are measured,
with three in good agreement with theory and one affected by
blending. The λ5277/λ4943 branching ratio is discrepant by
&gt;3σ, indicating errors in the atomic data for the λ5277 line. A
least-squares minimization scheme is used to simultaneously derive
the temperature, T, and density, Ne, of the RR Tel
nebula, and the interstellar extinction, E(B-V), towards RR Tel
from the complete set of emission lines. The derived values are:
log T/K=4.50 ± 0.23, log Ne/cm-3=7.25 ±
0.05, and E(B-V)≤ 0.27. The extinction is not well-constrained by
the Fe vii lines, but is consistent with the more accurate value
E(B-V)=0.109+0.052-0.059 derived here from
the Ne v λ2974/λ1574 ratio in the STIS spectrum. Large differences
between the K. A. Berrington et al. electron excitation data and the
earlier F. P. Keenan &amp; P. H. Norrington data-set are demonstrated,
and the latter is shown to give worse agreement with observations.

---------------------------------------------------------
Title: The CHIANTI database
Authors: Landi, E.; Dere, K. P.; Young, P. R.; Landini, M.; Mason,
H. E.; Del Zanna, G.
2005HiA....13..653L Altcode:
CHIANTI is a database of atomic data and transition rates necessary for
calculating synthetic spectra and carrying out plasma diagnostics of
astrophysical sources in the X-ray EUV and UV wavelength ranges. CHIANTI
includes both line and continuum emission from all astrophysically
abundant elements in the universe. All data are taken from refereed
literature and are critically assessed. CHIANTI also includes a suite
of IDL programs that allow spectroscopic analysis to be carried
out. CHIANTI data and software are freely distributed over the
internet. In the present talk I will describe the contents of
the CHIANTI database its current status and the areas where CHIANTI
is being developed and I will also present a comparison of CHIANTI
predictions with the X-ray emission from astrophysical sources.

---------------------------------------------------------
Title: Far Ultraviolet Spectroscopic Explorer Observations of the
Symbiotic Star AG Draconis
Authors: Young, P. R.; Dupree, A. K.; Espey, B. R.; Kenyon, S. J.;
Ake, T. B.
2005ApJ...618..891Y Altcode:
Spectra of the bright symbiotic star AG Draconis (BD +67°922) in
the wavelength range 905-1187 Å obtained with the Far Ultraviolet
Spectroscopic Explorer (FUSE) are presented. The spectra show a number
of narrow, nebular emission lines, together with a uniform continuum
from the hot component of the system, and numerous interstellar
absorption lines. We infer the existence of Ne VIII in the AG Dra nebula
through the identification of the Ne VII λ973.3 recombination line. The
emission-line spectrum is dominated by intense lines of O VI but also
shows weaker lines from highly ionized ions including Ne V, Ne VI,
S IV, and S VI. Members of the He II Balmer series can be identified
up to n=20. Lines of Fe II and Fe III fluoresced by O VI λ1032 are
identified at wavelengths 1141.172 and 1142.429 Å, respectively. The
emission lines are shown to be produced in a plasma with an electron
temperature of 20,000-30,000 K, photoionized by the white dwarf. The
Ne VI λ997/λ999 ratio shows that this ion and all others except
perhaps Ne VII are formed at least 300 white dwarf radii from the white
dwarf. Revised wavelengths for the Ne V 2s22p2
3P0,1-2s2p3 5S2
and Ne VI 2s22p 2P-2s2p2 4P
transitions are published.

---------------------------------------------------------
Title: Recent development of the CHIANTI database in the X-ray
wavelength range
Authors: Landi, E.; Dere, K. P.; Mason, H. E.; Del Zanna, G.; Landini,
M.; Young, P. R.
2004AAS...204.7310L Altcode: 2004BAAS...36R.801L
CHIANTI consists of a database of critically assessed atomic data
and transition rates to calculate line and continuum emission
from astrophysical plasmas. During the last year the CHIANTI
database has been substantially expanded in the X-ray wavelength
region by including a large number of new configurations and lines,
and by including ionization and recombination processes in the level
population calculations. We will describe these improvements,
the data we used, and illustrate examples of 1) their effects on
predicted emissivities and on plasma diagnostics 2) applications to
the study of flares in solar active regions

---------------------------------------------------------
Title: Radiative data for Fe XIII
Authors: Young, P. R.
2004A&A...417..785Y Altcode:
New radiative data for allowed and forbidden transitions between the
3s23p2, 3s3p3 and 3s23p3d
configurations of Fe XIII are presented. The calculations are performed
with the SSTRUCT atomic code, including 24 configurations in the
model, and term energy corrections have been applied to optimise the
theoretical level energies. The new data-set is compared with other
calculations in the literature and also an unpublished calculation
of Young that is found in the CHIANTI atomic database. Good agreement
is found in all cases except with calculations of Nahar. Comparisons
are also presented with laboratory and solar experimental data that
demonstrate the accuracy of the present calculations. The new data
are to be added to version 5 of the CHIANTI atomic database.

---------------------------------------------------------
Title: FUSE Observations of the Symbiotic Star AG Draconis
Authors: Young, P. R.; Dupree, A. K.; Espey, B. R.; Kenyon, S. J.;
Ake, T. B.
2004astro.ph..4459Y Altcode:
Spectra of the bright symbiotic star AG Draconis (BD+67D922) in
the wavelength range 905-1187 A obtained with the Far Ultraviolet
Spectroscopic Explorer (FUSE) are presented. The spectra show a number
of narrow, nebular emission lines, together with a uniform continuum
from the hot component of the system, and numerous interstellar
absorption lines. We infer the existence of Ne VIII in the AG Dra
nebula through the identification of the Ne VII 973.3 A recombination
line. The emission line spectrum is dominated by intense lines of O VI,
but also shows weaker lines from highly-ionized ions including Ne V,
Ne VI, S IV, S VI. Members of the He II Balmer series can be identified
up to n=20. Lines of Fe II and Fe III fluoresced by O VI 1032 are
identified at wavelengths 1141.172 A and 1142.429 A, respectively. The
emission lines are shown to be produced in a plasma with an electron
temperature of 20-30,000 K, photoionized by the white dwarf. The Ne VI
997/999 ratio shows that this ion and all others except perhaps Ne VII
are formed at least 300 white dwarf radii from the white dwarf. Revised
wavelengths for the Ne V 2s^2 2p^2 ^3P_0,1 - 2s 2p^3 ^5S_2 and Ne VI
2s^2 2p ^2P_J - 2s 2p^2 ^4P_J' transitions are published.

---------------------------------------------------------
Title: Intense Blinker in Active Regions
Authors: Young, P. R.
2004ESASP.547..257Y Altcode: 2004soho...13..257Y
A particular class of active region brightenings seen with the Coronal
Diagnostic Spectrometer on SOHO show transition region emission
lines enhanced by factors of around 1000 over quiet Sun values. The
brightenings have high density ( 1012 cm-3 ) and are estimated to be
around 0.1-0.2 arcsec in size. They are predominantly found in active
regions whose magnetic structure is rapidly evolving. High cadence
time sequences yield lifetimes of around 5 mins.

---------------------------------------------------------
Title: The element abundance FIP effect in the quiet Sun
Authors: Young, P. R.
2004cosp...35..957Y Altcode: 2004cosp.meet..957Y
The Coronal Diagnostic Spectrometer onboard SOHO is unique amongst solar
spectroscopy missions in being able to study the 'FIP effect' in quiet
Sun regions on the solar disk. Measurements of Mg/Ne EUV emission line
ratios over a 2 year period (1996-1998) will be presented and compared
with changes in the emission measure, temperature and density of the
quiet Sun over this time. Supergranule cell centre and network regions
will be compared and contrasted.

---------------------------------------------------------
Title: CHIANTI -- An Atomic Database for UV and X-ray Cool star
spectroscopy
Authors: Young, P. R.; Landi, E.; Bromage, G. E.; del Zanna, G.;
Dere, K. P.; Landini, M.; Mason, H. E.
2003csss...12.1119Y Altcode:
The CHIANTI atomic database was first released in 1996 and has since
become the standard resource for the interpretation of UV spectra
from the transition regions and coronae of the Sun and other cool
stars. We describe the contents of the most recent release (v.3)
and some of the uses that have been found for the database.

---------------------------------------------------------
Title: A Far Ultraviolet Spectroscopic Explorer Survey of Coronal
Forbidden Lines in Late-Type Stars
Authors: Redfield, Seth; Ayres, Thomas R.; Linsky, Jeffrey L.; Ake,
Thomas B.; Dupree, A. K.; Robinson, Richard D.; Young, Peter R.
2003ApJ...585..993R Altcode: 2002astro.ph.11363R
We present a survey of coronal forbidden lines detected in Far
Ultraviolet Spectroscopic Explorer (FUSE) spectra of nearby stars. Two
strong coronal features, Fe XVIII λ974 and Fe XIX λ1118, are
observed in 10 of the 26 stars in our sample. Various other coronal
forbidden lines, observed in solar flares, also were sought but
not detected. The Fe XVIII feature, formed at logT=6.8 K, appears
to be free of blends, whereas the Fe XIX line can be corrupted by
a C I multiplet. FUSE observations of these forbidden iron lines at
spectral resolution λ/Δλ~15,000 provides the opportunity to study
dynamics of hot coronal plasmas. We find that the velocity centroid
of the Fe XVIII feature deviates little from the stellar rest frame,
confirming that the hot coronal plasma is confined. The observed line
widths generally are consistent with thermal broadening at the high
temperatures of formation and show little indication of additional
turbulent broadening. The fastest rotating stars, 31 Com, α Aur Ab,
and AB Dor, show evidence for excess broadening beyond the thermal
component and the photospheric vsini. The anomalously large widths in
these fast-rotating targets may be evidence for enhanced rotational
broadening, consistent with emission from coronal regions extending
an additional ΔR~0.4-1.3R* above the stellar photosphere,
or represent the turbulent broadening caused by flows along magnetic
loop structures. For the stars in which Fe XVIII is detected, there is
an excellent correlation between the observed Röntgensatellit (ROSAT)
0.2-2.0 keV soft X-ray flux and the coronal forbidden line flux. As
a result, Fe XVIII is a powerful new diagnostic of coronal thermal
conditions and dynamics that can be utilized to study high-temperature
plasma processes in late-type stars. In particular, FUSE provides the
opportunity to obtain observations of important transition region
lines in the far-UV, as well as simultaneous measurements of soft
X-ray coronal emission, using the Fe XVIII coronal forbidden line.

---------------------------------------------------------
Title: Boundary Conditions for Stellar Convection (invited review)
Authors: Arnett, D.; Young, P.; Knierman, K. A.; Rigby, J. R.
2003ASPC..304..342A Altcode: 2003cnou.conf..342A
No abstract at ADS

---------------------------------------------------------
Title: CHIANTI-An Atomic Database for Emission Lines. VI. Proton
Rates and Other Improvements
Authors: Young, P. R.; Del Zanna, G.; Landi, E.; Dere, K. P.; Mason,
H. E.; Landini, M.
2003ApJS..144..135Y Altcode: 2002astro.ph..9493Y
The CHIANTI atomic database contains atomic energy levels, wavelengths,
radiative transition probabilities, and electron excitation data for
a large number of ions of astrophysical interest. Version 4 has been
released, and proton excitation data are now included, principally
for ground configuration levels that are close in energy. The fitting
procedure for excitation data, both electrons and protons, has been
extended to allow nine-point spline fits in addition to the previous
five-point spline fits. This allows higher quality fits to data from
close-coupling calculations where resonances can lead to significant
structure in the Maxwellian-averaged collision strengths. The effects
of photoexcitation and stimulated emission by a blackbody radiation
field in a spherical geometry on the level balance equations of
the CHIANTI ions can now be studied following modifications to the
CHIANTI software. With the addition of H I, He I, and N I, the first
neutral species have been added to CHIANTI. Many updates to existing
ion data sets are described, while several new ions have been added
to the database, including Ar IV, Fe VI, and Ni XXI. The two-photon
continuum is now included in the spectral synthesis routines, and a
new code for calculating the relativistic free-free continuum has been
added. The treatment of the free-bound continuum has also been updated.

---------------------------------------------------------
Title: CHIANTI - An Atomic Database for XUV Emission Lines
Authors: Landi, Enrico; Dere, Ken P.; Landini, Massimo; Young, Peter
R.; Mason, Helen E.; del Zanna, Giulio
2003IAUJD..17E..10L Altcode:
CHIANTI is a database of atomic data and transition rates necessary for
calculating synthetic spectra and carrying out plasma diagnostics of
astrophysical sources in the X-ray EUV and UV wavelength ranges. CHIANTI
includes both line and continuum emission from all astrophysically
abundant elements in the universe. All data are taken from refereed
literature and are critically assessed. CHIANTI also includes a suite
of IDL programs that allow spectroscopic analysis to be carried
out. CHIANTI data and software are freely distributed over the
internet. In the present talk I will describe the contents of
the CHIANTI database its current status and the areas where CHIANTI
is being developed and I will also present a comparison of CHIANTI
predictions with the X-ray emission from astrophysical sources.

---------------------------------------------------------
Title: AG Draconis - a High Density Plasma Laboratory
Authors: Young, Peter R.; Espey, Brian; Kenyon, Scott J.; Dupree,
Andrea K.
2003IAUJD..20E..22Y Altcode:
A program to take high resolution optical and UV spectra of the
symbiotic star AG Draconis is taking place in early 2003. AG Dra has an
extremely bright high density nebula ionized by a hot white dwarf and
the spectra will be used as a testing ground for photoionization codes
such as Cloudy and XSTAR. These codes are used routinely in the study
of photoionized plasmas and there is a need for them to be accurately
'calibrated' for stable bright systems. The density of the AG Dra
nebula is typical of the emission line regions of active galactic
nuclei and stellar atmospheres. Several new plasma diagnostics will be
available through combining FUSE (900-1200Å) and HST/STIS (1200-3000Å)
UV spectra while the high resolution of these instruments will enable
outflow in the nebula to be studied in unprecedented detail through
emission line profiles.

---------------------------------------------------------
Title: A Far Ultraviolet Spectroscopic Explorer Survey of Late-Type
Dwarf Stars
Authors: Redfield, Seth; Linsky, Jeffrey L.; Ake, Thomas B.; Ayres,
Thomas R.; Dupree, A. K.; Robinson, Richard D.; Wood, Brian E.; Young,
Peter R.
2002ApJ...581..626R Altcode:
We describe the 910-1180 Å spectra of seven late-type dwarf stars
obtained with the Far Ultraviolet Spectroscopic Explorer (FUSE)
satellite. The stars include Altair (A7 IV), Procyon (F5 IV-V), α
Cen A (G2 V), AB Dor (K1 V), α Cen B (K2 V), ɛ Eri (K2 V), and AU
Mic (M0 V). We present line identifications, fluxes, Doppler shifts,
and widths. Doppler shifts are measured with respect to heliocentric
wavelength scales determined from interstellar absorption lines, and
are compared with transition region line shifts seen in Hubble Space
Telescope (HST) ultraviolet spectra. For the warmer stars the O VI lines
extend the trend of increasing redshift with line formation temperature,
but for the cooler stars the O VI line redshifts are essentially
zero. The C III and O VI lines of most stars in the sample are best
fit with two Gaussians, and we confirm the correlation of increasing
importance of the broad component with increasing stellar activity. The
nonthermal velocities of the narrow component are subsonic and exhibit
a trend toward larger velocities with decreasing surface gravity, while
the nonthermal velocities of the broad components show no obvious trend
with stellar gravity. The C III and O VI lines of Altair show unique
broad horned profiles. Two flares were observed on AU Mic. One shows
increasing continuum flux to shorter wavelengths, which we interpret as
free-free emission from hot plasma, and relatively narrow, redshifted
C III and O VI emission. The other shows very broad line profiles.

---------------------------------------------------------
Title: AG Dra -- a high density plasma laboratory
Authors: Young, Peter
2002hst..prop.9510Y Altcode: 2002hst..prop.5857Y
A STIS observation of the symbiotic star AG Draconis yielding spectra in
the range 1150--10 000 Angstrom is requested. AG Dra is a non-eclipsing
binary that shows strong, narrow nebular emission lines that originate
in the wind of a K giant, photoionized by a hot white dwarf. The
density of the nebula is around 10^10 electrons/cm^3 and is the perfect
laboratory for testing the plasma modeling codes cloudy and xstar at
high densities. These codes are used for a wide range of astrophysical
objects including stellar winds, accretion disks, active galactic nuclei
and Seyfert galaxies, and calibrating them against high signal-to-noise
spectra from comparatively simple systems is essential. AG Dra is
the perfect high density laboratory for this work. In addition, many
previously undetected emission lines will be found through the high
sensitivity of STIS, which will allow new plasma diagnostics to be
tested. These twin objectives are particularly pertinent as the high
sensitivity of emphHST/COS will will permit similar high resolution
spectroscopy to be applied to a whole new regime of extragalactic
objects. By combining far-UV data from Ause with complementary data
from STIS, we will determine ratios of emission lines from the same ion,
or ions of similar ionization level. These will permit a more complete
set of diagnostics than are obtainable from one instrument alone.

---------------------------------------------------------
Title: X-Ray Doppler Imaging of Stellar Coronae
Authors: Brickhouse, Nancy S.; Dupree, Andrea K.; Young, Peter
2002APS..APRB17059B Altcode:
Chandra HETG observations of the bright eclipsing contact binary 44
Boo show X-ray line profiles which are Doppler-shifted by orbital
motions. The observation continuously covers 2.56 epochs. Although
significant variability is found in the light curve, no clear eclipses
are observed. The phase-binned line profiles, in conjunction with the
X-ray light curve, constrain the coronal structures to be localized at
high latitude. These observations demonstrate the power of the X-ray
Doppler imaging technique. Studies of other contact binaries, and
studies of RS CVn systems with future X-ray spectrometers are discussed.

---------------------------------------------------------
Title: The Capella Giants and Coronal Evolution across the Hertzsprung
Gap
Authors: Johnson, O.; Drake, J. J.; Kashyap, V.; Brickhouse, N. S.;
Dupree, A. K.; Freeman, P.; Young, P. R.; Kriss, G. A.
2002ApJ...565L..97J Altcode:
We present an analysis of the coronal line Fe XXI λ1354 observed
in medium-resolution Hubble Space Telescope/Space Telescope Imaging
Spectrograph echelle spectra of Capella obtained on 1999 September
12. These data were collected in support of a multiwavelength
spectroscopic campaign designed to provide detailed temperature and
density diagnostics over a wide range of temperatures, and they are
accompanied by simultaneous Chandra, Extreme Ultraviolet Explorer,
BeppoSAX, and Very Large Array observations. The line Fe XXI λ1354
formed at 107 K is crucial to the interpretation of these
data sets since it allows the deconvolution of the coronal flux of the
two binary components. While earlier observations implied comparable
coronal emission from both stars, our data indicate that nearly
all the Fe XXI flux in the C I/Fe XXI blend at 1354 Å arises from
the rapidly rotating G1 III secondary. This suggests a significant
decline in the hottest part of the corona of the G8 III primary over
the past 5 years. For the first time, we can assign the variability
of the high-temperature X-rays to the cooler He core burning star in
the system. This result suggests that nascent coronae in the early
Hertzsprung gap phase apparently do not vary and that cyclic activity
and strong variability are seen only in later evolutionary stages when
dynamos are more developed in deeper convective envelopes.

---------------------------------------------------------
Title: Capella: Separating the Giants
Authors: Young, P. R.; Dupree, A. K.
2002ApJ...565..598Y Altcode:
Images from the Faint Object Camera (FOC) on the Hubble Space Telescope
(HST) are used to spatially separate the two giants of Capella (α
Aurigae; HD 34029) for the first time at ultraviolet wavelengths. The
images were obtained with broadband filters that isolate the wavelength
regions 2500-3000 Å and 1300-1500 Å. The cool G8 giant is found
to be weaker than the hot G1 giant by factors of around 4 and 17,
respectively, in these bands. The latter factor is largely due to the
much stronger G1 continuum at short wavelengths. No evidence is found
for material lying between the two stars in the images. In addition,
the objective prisms of the FOC were used to obtain low-resolution
spectra from 1200 to 3000 Å, allowing individual emission lines from
each star to be spatially separated. Cool-to-hot star ratios for the
emission lines H I Lyα, O I λ1305, Si II λ1816, C II λ1335, He II
λ1640, and Si IV λ1393 are presented, showing that the cool giant
is weaker than the hot giant by factors of 5-10 in these lines. The
O I emission is only a factor of 2.5 weaker in the cool giant, most
probably resulting from fluorescence in the extended atmosphere of
the cool giant. The line ratios are compared with values derived from
International Ultraviolet Explorer and HST/Goddard High Resolution
Spectrograph spectra, which could separate the stars spectrally but
not spatially. Reasonable agreement is found although the FOC ratios
generally imply lower contributions from the cool giant. Based on
observations with the NASA/ESA Hubble Space Telescope obtained at the
Space Telescope Science Institute, which is operated by AURA, Inc.,
under NASA contract NAS 5-26555.

---------------------------------------------------------
Title: RR Tel getting under the flux limit -- an observation with FUSE
Authors: Young, Peter R.
2002fuse.prop.C141Y Altcode:
The symbiotic star RR Telescopii holds a special place amongst UV
spectroscopists due to the extraordinary richness of the emission line
spectrum emitted by the nebula around the system, which has proved to
be an extremely fruitful laboratory for both plasma modeling and line
identification. FUSE will obtain, for the first time, a high spectral
resolution spectrum in the 900-1100 A region at high sensitivity. RR Tel
has not previously been considered for observing with FUSE on account
of the O VI line fluxes being well above the FUSE flux limits. A way
to observe RR Tel safely with FUSE by only obtaining spectra through
the SiC channels is outlined in the feasibility section that follows.

---------------------------------------------------------
Title: The CHIANTI Atomic Database and Instrument Calibration:
a Symbiosis
Authors: Mason, H. E.; Del Zanna, G.; Dere, K. P.; Landi, E.; Landini,
M.; Young, P. R.
2002ISSIR...2..271M Altcode: 2002ESASR...2..271M; 2002rcs..conf..271M
The CHIANTI atomic database comprises a comprehensive, accurate and
up-to-date database of atomic parameters, necessary for emission-line
spectroscopy. The suite of user-friendly software allows plasma
diagnostics to be carried out. Since its release in 1996, CHIANTI has
become a standard resource for the analysis of solar spectra. Accurate
atomic data can provide the foundation for in-flight instrument
calibrations. Conversely, an accurate instrument calibration can provide
a check on atomic parameters. The internal consistency of spectral-line
intensities can be used to highlight specific anomalies. In this paper,
we illustrate how CHIANTI has been used to validate the calibration of
solar EUV instruments: SOHO-CDS, -SUMER, -EIT and SERTS. In addition,
we show how anomalous spectral-line intensities indicate the need for
more accurate atomic calculations.

---------------------------------------------------------
Title: FUSE Survey of Cool Luminous Stars
Authors: Dupree, A. K.; Young, P. R.; Lobel, A.; Ake, T. R.; Linsky,
J. L.; Redfield, S.; FUSE Cool Star Team
2001AAS...199.1310D Altcode: 2001BAAS...33.1328D
The FUSE telescope has been used to survey spectroscopically eight
cool luminous stars (β Cet, α Ori,α Tau, α Car, β Gem, 31 Com,
β Dra, α Aqr) in the spectral region λ λ 910--1180. Emission from
O VI has been detected in all stars with the exception of α Ori,
decreasing in surface flux across the giant branch. This demonstrates
the pervasive extent of high temperature plasma ( ~ 3x 105K)
to stars as late as K5 III (α Tau). Densities in the lower transition
region ( ~ 70000K), as determined from C III line ratios, are on the
order of 109 cm-3, with densities in the active
stars 31 Com and β Cet perhaps as much as an order of magnitude
higher. Emission from coronal plasma represented by Fe XVIII occurs
in β Cet. Line profiles of individual species can be used to infer
atmospheric heating and dynamics. Extended atmospheres are signaled by
the presence of narrow Fe II emission that is fluoresced by H-Lyman α
in the coolest stars including α Ori. These rich spectra document the
energetics and dynamics of giant and supergiant atmospheres. Based on
Guaranteed Team observations made with the NASA-CNES-CSA Far Ultraviolet
Explorer which is operated for NASA by The Johns Hopkins University
under NASA contract NAS5-32985.

---------------------------------------------------------
Title: The orbital light curve of aquila X-1
Authors: Robinson, E. L.; Welsh, W. F.; Young, P.
2001AIPC..599..902R Altcode: 2001xase.conf..902R
The R-band light curve of the X-ray nova/neutron-star binary Aql
X-1 is dominated by ellipsoidal variations when it is at quiescence,
although the ellipsoidal variations are severely distorted and have
unequal maxima. The peak-to-peak amplitude of the variations is ~
0.25 mag. The orbital period measured from the ellipsoidal variations
is consistent with the 18.95 hr period measured by Chevalier &amp;
Ilovaisky (1998); and the orbital inclination must be greater than 36°,
and probably lies between 36° and 55°. During outbursts the light
curve of Aql X-1 is dominated by the “reflection effect,” that is,
by heating of the side of the companion star facing the neutron star. .

---------------------------------------------------------
Title: A Survey of Nearby Cool Dwarf Star Spectra Obtained by FUSE
Authors: Redfield, S.; Linsky, J. L.; Dupree, A. K.; Young, P. R.;
Lobel, A.; Ake, T. B.; FUSE Cool Star Team
2001AAS...199.1312R Altcode: 2001BAAS...33.1329R
We present the cool star dwarf spectra obtained by the FUSE Science Team
using the Far Ultraviolet Spectroscopic Explorer (FUSE). The survey
includes the stars α Aql, α Cen A, α Cen B, ɛ Eri, AU Mic, and AB
Dor. The spectral range extends from 900 to 1200 ~Å, at a spectral
resolution of λ /Δ λ ~ 20,000. Numerous emission lines are present
and identified. Lines of particular interest, such as C III (977 Å),
O VI (1032 and 1038 Å), and the Lyman series, are present in all stars
and studied in detail. The forbidden coronal Fe XVIII (975 Å) line is
present in some spectra and is useful in studying the dynamics of the
107 K coronal plasma. Absorption by warm Local Interstellar
Medium (LISM) gas is visible in several lines, such as C III (977 Å)
and C II (1037 Å). Combined with LISM absorption studies of the same
stars at longer wavelengths (ie. using spectrographs aboard the Hubble
Space Telescope (HST)), the FUSE LISM absorption can provide important
insights into the structure of the nearby warm ISM. This atlas of
nearby cool stars in the far-ultraviolet provides important information
pertaining to the atmospheres of dwarf stars and will be a useful tool
in planning future observations of cool stars. This work is based on
data obtained for the Guaranteed Time Team by the NASA-CNES-CSA FUSE
mission operated by the Johns Hopkins Observatory. Financial support
to U.S. participants has been provided by NASA contract NAS5-32985.

---------------------------------------------------------
Title: X-Ray Doppler Imaging of Stellar Coronae
Authors: Brickhouse, N. S.; Dupree, A. K.; Young, P. R.
2001AAS...19911202B Altcode: 2001BAAS...33Q1478B
Chandra HETG observations of the bright eclipsing contact binary 44
Boo show X-ray line profiles which are Doppler-shifted by orbital
motions. The observation continuously covers 2.56 epochs. Although
significant variability is found in the light curve, no clear eclipses
are observed. The phase-binned line profiles, in conjunction with the
X-ray light curve, constrain the coronal structures to be localized at
high latitude. These observations demonstrate the power of the X-ray
Doppler imaging technique. Studies of other contact binaries, and
studies of RS CVn systems with future X-ray spectrometers are discussed.

---------------------------------------------------------
Title: A Relationship Between Transition Region Brightenings,
Abundances, and Magnetic Topology
Authors: Fletcher, Lyndsay; López Fuentes, Marcelo C.; Mandrini,
Cristina H.; Schmieder, Brigitte; Démoulin, Pascal; Mason, Helen E.;
Young, Peter R.; Nitta, Nariaki
2001SoPh..203..255F Altcode:
We present multi-instrument observations of active region (AR) 8048,
made between 3 June and 5 June 1997, as part of the SOHO Joint Observing
Program 33. This AR has a sigmoid-like global shape and undergoes
transient brightenings in both soft X-rays and transition region
(TR) lines. We compute a magneto-hydrostatic model of the AR magnetic
field, using as boundary condition the photospheric observations of
SOHO/MDI. The computed large-scale magnetic field lines show that the
large-scale sigmoid is formed by two sets of coronal loops. Shorter
loops, associated with the core of the SXT emission, coincide with
the loops observed in the hotter CDS lines. These loops reveal a
gradient of temperature, from 2 MK at the top to 1 MK at the ends. The
field lines most closely matching these hot loops extend along the
quasi-separatrix layers (QSLs) of the computed coronal field. The TR
brightenings observed with SOHO/CDS can also be associated with the
magnetic field topology, both QSL intersections with the photosphere,
and places where separatrices issuing from bald patches (sites where
field lines coming from the corona are tangent to the photosphere)
intersect the photosphere. There are, furthermore, suggestions that
the element abundances measured in the TR may depend on the type
of topological structure present. Typically, the TR brightenings
associated with QSLs have coronal abundances, while those associated
with BP separatrices have abundances closer to photospheric values. We
suggest that this difference is due to the location and manner in which
magnetic reconnection occurs in two different topological structures.

---------------------------------------------------------
Title: X-Ray Doppler Imaging of 44i Bootis with Chandra
Authors: Brickhouse, N. S.; Dupree, A. K.; Young, P. R.
2001ApJ...562L..75B Altcode: 2001astro.ph.10560B
Chandra High-Energy Transmission Grating observations of the bright
eclipsing contact binary 44i Bootis show X-ray line profiles that
are Doppler-shifted by orbital motions. The X-ray emission spectrum
contains a multitude of lines superposed on a weak continuum, with
strong lines of O VIII, Ne X, Fe XVII, and Mg XII. The profiles of these
lines from the total observed spectrum show Doppler-broadened widths
of ~550 km s-1. Line centroids vary with orbital phase,
indicating velocity changes of greater than 180 km s-1. The
first-order light curve shows significant variability but no clear
evidence for either primary or secondary eclipses. Flares are
observed for all spectral ranges; additionally, the light curve
constructed near the peak of the emission measure distribution
[Te=(5-8)×106 K] shows quiescent variability
as well as flares. The phase dependences of line profiles and light
curves together imply that at least half of the emission is localized
at high latitude. A simple model with two regions on the primary star
at relatively high latitude reproduces the observed line profile shifts
and quiescent light curve. These first clear X-ray Doppler shifts of
stellar coronal material illustrate the power of Chandra.

---------------------------------------------------------
Title: Far Ultraviolet Spectroscopic Explorer Observations of Capella
Authors: Young, P. R.; Dupree, A. K.; Wood, B. E.; Redfield, S.;
Linsky, J. L.; Ake, T. B.; Moos, H. W.
2001ApJ...555L.121Y Altcode:
Far Ultraviolet Spectroscopic Explorer observations of the binary
system Capella reveal a rich emission-line spectrum containing neutral
and ionic species, among them H I, O I, C III, O VI, S VI, Ne V,
and Ne VI. In addition, Fe XVIII λ974.85, formed at temperatures
of ~6×106 K, is detected. Whereas the strong transition
region lines principally come from the G1 giant, consistent with results
from previous ultraviolet observations, Fe XVIII is formed largely in
the G8 giant atmosphere. Line ratios from C III suggest densities of
(2-8)×1010 cm-3, although anomalous line profiles
of the 1176 Å transition may signal optical depth effects. Based on
observations made with the NASA-CNES-CSA Far Ultraviolet Spectroscopic
Explorer, which is operated for NASA by Johns Hopkins University under
NASA contract NAS5-32985.

---------------------------------------------------------
Title: Detection of Chlorine Ions in the Far Ultraviolet Spectroscopic
Explorer Spectrum of the Io Plasma Torus
Authors: Feldman, Paul D.; Ake, Thomas B.; Berman, Alice F.; Moos,
H. Warren; Sahnow, David J.; Strobel, Darrell F.; Weaver, Harold A.;
Young, Peter R.
2001ApJ...554L.123F Altcode:
The spectrum of the Io plasma torus in the range of 995-1187 Å was
recorded at 0.26 Å resolution by the Far Ultraviolet Spectroscopic
Explorer (FUSE) on 2000 January 20. Five orbits of data were
obtained in point-and-shoot mode (no tracking of the moving
target), with the east ansa of the torus initially centered in the
30”×30” aperture of the FUSE LiF spectrographs
yielding a total observation time of 3405 s. The spectral resolution
exceeds by a factor of 10 that of the data obtained by the Hopkins
Ultraviolet Telescope (HUT) during the Astro-1 mission. This region of
the spectrum is dominated by resonance multiplets of S III and S IV,
whose multiplet structures are nearly completely resolved, as well as
numerous S II multiplets originating on the 2Do
state of the ground configuration. Weak emission from a few lines of
the resonance multiplets of Cl III and Cl II is detected at or above
the 3 σ level, Cl III being stronger with two components roughly
one-tenth the brightness of the main components of S III λ1018. We
derive an abundance of Cl+2 of 3% relative to S+2,
leading to an overall chlorine ion abundance in the torus of ~1%. The
ratio of S IV to S III brightness is about twice that observed by HUT,
which, when the different slit geometries are accounted for, supports
the earlier analysis that S IV emissions originate from a region more
extended out of the centrifugal plane than the S III emissions.

---------------------------------------------------------
Title: CHIANTI-An Atomic Database for Emission Lines. IV. Extension
to X-Ray Wavelengths
Authors: Dere, K. P.; Landi, E.; Young, P. R.; Del Zanna, G.
2001ApJS..134..331D Altcode:
CHIANTI provides a database of atomic energy levels, wavelengths,
radiative transition probabilities, and electron excitation data for
a large number of ions of astrophysical interest. It also includes a
suite of Interactive Data Language programs to calculate optically
thin synthetic spectra and to perform spectral analysis and plasma
diagnostics. This database allows the calculation of theoretical line
emissivities necessary for the analysis of optically thin emission-line
spectra. The first version (1.01) of the CHIANTI database was released
in 1996 and published by Dere et al. in 1997 as Paper I in this
series. The second version, released in 1999 by Landi et al., included
continuum emission and data for additional ions. Both versions of the
CHIANTI database have been used extensively by the astrophysical and
solar communities to analyze emission-line spectra from astrophysical
sources. Now the CHIANTI database has been extended to wavelengths
shorter than 50 Å by including atomic data for the hydrogen and helium
isoelectronic sequences, inner-shell transitions and satellite lines,
and several other ions. In addition, some of the ions already present
in the database have been updated and extended with new atomic data
from published calculations.

---------------------------------------------------------
Title: CHIANTI - an atomic database for emission lines, Paper 4:
Extension to X-ray Wavelengths
Authors: Dere, K. P.; Landi, E.; Young, P. R.; Del Zanna, G.
2001AGUSM..SP21B08D Altcode:
CHIANTI provides a database of atomic energy levels, wavelengths,
radiative transition probabilities and electron excitation data for
a large number of ions of astrophysical interest. It also includes
a suite of Interactive Data Language (IDL) programs to calculate
optically thin synthetic spectra and to perform spectral analysis and
plasma diagnostics. This database allows the calculation of theoretical
line emissivities necessary for the analysis of optically thin emission
line spectra. The first version of the CHIANTI database was released
in 1996 (Dere et al., 1996). The second version, released in 1999,
included continuum emission and data for additional ions (Landi
et al. 1999). Both versions of the CHIANTI database have been used
extensively by the astrophysical and solar communities to analyze
emission line spectra from astrophysical sources. Now the CHIANTI
database has been extended to wavelengths shorter than 50Å by including
atomic data for the hydrogen and helium isoelectronic sequences,
inner-shell transitions and satellite lines and several other ions. In
addition, some of the ions already present in the database have been
updated and extended with new atomic data from published calculations.

---------------------------------------------------------
Title: FUSE Observations of Capella
Authors: Young, P. R.; Dupree, A. K.; Wood, B. E.; Redfield, S.;
Linsky, J. L.; Ake, T. B.; Moos, H. W.
2001astro.ph..3261Y Altcode:
Far Ultraviolet Spectroscopic Explorer FUSE observations of the bright
binary system Capella (Alpha Aurigae; G1 III + G8 III) reveal a rich
emission line spectrum containing neutral and ionic species, among
them H I, O I, C III, O VI, S VI, Ne V and Ne VI. In addition the Fe
XVIII 974.85 A line, formed at temperatures of approx. 6 x 10^6 K,
is detected. Whereas the chromospheric and transition region emission
is dominated by that from the G1 giant, consistent with results from
previous ultraviolet observations, Fe XVIII is formed largely in the
G8 giant atmosphere. Line ratios from C III suggest densities of 2-8
x 10^10 cm^-3, although anomalous line profiles of the 1176 transition
may signal optical depth effects. The hydrogen Lyman series, detected
for the first time, displays asymmetric emission consistent with an
expanding atmosphere.

---------------------------------------------------------
Title: AG Draconis (BD +67 922) Follow-up
Authors: Young, Peter
2001fuse.prop.P248Y Altcode:
AG Draconis is a symbiotic star consisting of a K giant and white
dwarf. The UV is dominated by emission lines from a nebula believed to
be around the white dwarf. AG Dra was observed by FUSE on 16-March-2000
as part of the science verification program for FUSE. This short
(~2400s) observation produced a high quality spectrum revealing emission
lines from several species, including O VI, Ne V, Ne VI, S IV, S VI
and He II. A further observation of AG Dra is planned to determine the
geometry of the nebula, attribute the wind to one of the two stars,
and to obtain a full exposure in the SiC channels which will be needed
to obtain a density for the nebula.

---------------------------------------------------------
Title: 44i Bootis (HD 133640)
Authors: Young, Peter
2001fuse.prop.P247Y Altcode:
44i Boo is a W UMa type contact binary at a distance of 12.8 pc with
an orbital period of 6.4 hours and an inclination of 72.8 degrees,
so that there are two eclipses per orbit. X-ray and UV emission from
highly-ionised ions have revealed that 44i Boo exhibits a corona, but
that the emission levels are below those of rapidly rotating single
stars or short-period, detached binaries, indicating that the dynamo
is being inhibited by the physics associated with the contact. By
categorising in detail the nature of the corona of 44i Boo, one may
shed light on how the magnetic dynamo operates in stars. With FUSE it
will be possible to use the high spectral resolution and sensitivity
of the instrument to monitor line fluxes and profiles of the strong
C III 977 and O VI 1032 emission lines during the orbit, as well as
use the temperature coverage of these and weaker lines to compare with
the atmospheric models made with previous instruments.

---------------------------------------------------------
Title: CDS UV Brightenings Explained by Quasi-separatrices and Bald
Patches in an S-shape active region
Authors: Schmieder, B.; Démoulin, P.; Fletcher, L.; López Fuentes,
M. C.; Mandrini, C. H.; Mason, H. E.; Young, P. R.; Nitta, N.
2001IAUS..203..314S Altcode:
We present multi-instrument observations of AR 8048, made between
June 3 and June5 1997 as part of SoHO JOP033. This active region
has a sigmoid-like global shape and undergoes transient erupting
phenomena which releases the stored energy. Using a force free
field approach, we defined coronal magnetic field lines which fit
with the observations. The large-scale magnetic field lines confirms
the sigmoid characteristics of the active region. The study in 3D of
the configuration explained where and how the energy is released at
different places. The Ne VI brightenings correspond to the location
of tangent to the photosphere field lines, named "bald patch", they
are localized in the low transition region and represent feet of field
lines. The Si XII brightenings at coronal temperature are at the top
of coronal loops joining quasi-separatrices.

---------------------------------------------------------
Title: A FUSE Observation of the Symbiotic Star AG Draconis
Authors: Young, P. R.; Dupree, A. K.; Kenyon, S. J.; Espey, B.; Ake,
T. B.
2000AAS...197.0806Y Altcode: 2000BAAS...32.1406Y; 2000AAS...197..806Y
AG Draconis (BD+67o922) is a yellow symbiotic star,
consisting of a K0--K3 giant and hot compact object, thought to
be a white dwarf. The hot star photoionizes the wind of the giant,
giving a dense nebula rich in ionized species. The system undergoes
increases in brightness by up to 3 magnitudes at irregular intervals,
a phenomenon thought to be due to the triggering of nuclear burning
on the hot star after the accretion of a critical mass of material
from the giant wind. The Far Ultraviolet Spectroscopic Explorer (FUSE)
satellite observed AG Dra in March 2000 during a quiescent period. The
spectrum covered the range 905--1187 Å at a spectral resolution of ~
15--20,000, and exhibits a number of emission lines from highly-ionised
species, a continuum from the hot star, and absorption lines from
the interstellar medium. The O 6 λ λ 1032, 1038 emission lines
dominate the spectrum, with the λ 1032 line showing evidence of a
warm wind. Other species identified include Ne 5, Ne 6, S 4, S 6 and
the He 2 Balmer lines. These lines help constrain the radiation field
experienced by the nebula, and also the degree of extinction along
the line of sight to AG Dra. Measurements of the absorption lines of
molecular hydrogen and the atomic species are used to infer properties
of the interstellar medium in the direction of AG Dra. FUSE is a NASA
Origins mission operated by the Johns Hopkins University. Funding for
this work is provided through NASA contract NAS-532985.

---------------------------------------------------------
Title: FUSE Observations of K--M Stars
Authors: Ake, T. B.; Dupree, A. K.; Linsky, J. L.; Harper, G. M.;
Young, P. R.
2000AAS...19712903A Altcode: 2001BAAS...33Q.712A
As part of the FUSE PI program, a representative sample of cool stars
is being surveyed in the LWRS (30 x 30 arcsec) aperture. We report on
recent observations of three late-type stars, AU Mic (HD 197481, M0 Ve),
β Gem (HD 62509, K0 IIIb), and α Ori (HD 39801, M1-2 Ia--Iab). AU
Mic and β Gem show strong emission lines of O VI 1032/1037 and C III
977/1176 and weaker lines of C II, N II, N III, S IV, Si III, Si IV,
and perhaps Fe III. AU Mic has evidence of He II and S III emission,
and β Gem shows S I emission. Differences are seen in line ratios and
line profiles between these stars. In α Ori, these features are very
weak or non-existent, and Fe II fluorescent lines in the 1100-1150 Å
region, pumped by H I Lyman α , are present. Several emission lines
are still unidentified in all spectra. Prospects for future cool star
observations will be discussed. This work is based on data obtained for
the Guaranteed Time Team by the NASA-CNES-CSA FUSE mission operated by
the Johns Hopkins University. Financial support to U. S. participants
has been provided by NASA contract NAS5-32985.

---------------------------------------------------------
Title: FUSE Observations of Luminous Cool Stars
Authors: Dupree, A. K.; Young, P. R.; Ake, T. B.
2000AAS...197.4417D Altcode: 2000BAAS...32.1474D
Luminous cool stars can address the evolution of magnetic activity
and the dynamics of stellar winds and mass loss. The region of yellow
supergiants in the HR diagram contains stars of intermediate mass both
with coronas and those possessing a hot outer atmosphere in the presence
of a strong wind (the “hybrid” stars). These hybrid objects hold
particular significance for evolution studies because they represent the
physically important connection between solar-like stars (with coronas
and fast winds of low-mass loss rate) and the cool supergiant stars
(Alpha Ori-like) with cool outer atmospheres and massive winds. The Far
Ultraviolet Spectroscopic Explorer (FUSE) measured the chromospheric
and transition region emissions of the bright G2 Ib supergiant Beta
Draconis (HD 159181) on 9 May 2000. Two exposures through the large
aperture totaled 7695 s and were obtained in all channels covering
the region λ λ 912-1180. Emission from chromospheric and transition
region ions (C III, O VI, Si III, S IV, S VI) is detected along with
a number of low ion stages. Profiles of strong lines are asymmetric
suggesting the presence of a wind. A short exposure (3260 s) of Alpha
Aquarii (HD 209750), a hybrid supergiant also of spectral type G2 Ib
was obtained June 29, 2000. Dynamics of the atmospheres can be inferred
from line profiles. The atmospheric temperature distribution, densities,
and scale sizes can be evaluated from line fluxes to characterize the
differences between a coronal star and a hybrid supergiant. FUSE is a
NASA Origins mission operated by The Johns Hopkins University. Funding
for this research is provided through NASA Contract NAS-532985.

---------------------------------------------------------
Title: Observational Tests and Predictive Stellar Evolution
Authors: Young, P.; Mamajek, E.; Arnett, D.; Liebert, J.
2000AAS...19711401Y Altcode: 2000BAAS...32.1596Y
We present comparisons between the detached, double-line eclipsing
binaries of Andersen (1991), which have precisely determined masses and
radii, and stellar evolution models produced with the TYCHO code. A
set of eighteen binary systems were chosen which cover a range of
mass from 22.89 to 0.96 Msol. The error of the models in
Teff, luminosity and the time difference (between the best
fit models for each member of a pair) had dispersions of ~ 3%, 6%, and
10%, respectively, without optimization of parameters. This indicates
that the contributions to observable parameters from poorly constrained
(either theoretically or observationally) effects such as abundances,
rotation and convective overshooting are of order a few percent for
the majority of stars. The outlying stars provide candidates for
observations which may shed light on these effects. Pre-MS models
matched EK Cep B, a known post-T Tauri star and the PV Cas system,
comprised of peculiar late B/early A stars which have historically
proven difficult to fit (Pols et al., 1997). Estimates of the time
until Roche lobe overflow identified five systems which may begin mass
transfer when &lt; 10% older than their current age. The primary of
zeta Phe in particular appears to be especially close to Roche lobe
overflow, which may explain the difficulty in fitting conventional
stellar models to the system. Finally, the structural k constants were
calculated from the best fit models for a subset of eleven systems with
published apsidal motions. This work was supported in part by the DOE,
grant number DE-FG03-98DP00214/A001.

---------------------------------------------------------
Title: Detection of Chlorine Ions in the FUSE Spectrum of the Io
Plasma Torus
Authors: Feldman, P. D.; Ake, T. B.; Berman, A. F.; Moos, H. W.;
Sahnow, D. J.; Strobel, D. F.; Weaver, H. A.; Young, P. R.; FUSE
Solar System Team
2000DPS....32.3401F Altcode: 2000BAAS...32.1054F
The spectrum of the Io plasma torus in the range 995--1087 Å was
recorded at ~0.3 Å resolution by the Far Ultraviolet Spectroscopic
Explorer (FUSE) on January 20, 2000. Five orbits of data were obtained
in point-and-shoot mode (no tracking of the moving target) with the
East ansa of the torus initially centered in the 30” x 30” aperture
of the FUSE LiF spectrographs yielding a total observation time of 3405
seconds. The spectral resolution exceeds by a factor of ten that of
the data obtained by the Hopkins Ultraviolet Telescope (HUT) during the
Astro-1 mission (Moos et al., ApJ 382, L105, 1991). This region of the
spectrum is dominated by resonance multiplets of S 3 at 1018 Å and S
4 at 1070 Å, whose multiplet structure is nearly completely resolved,
as well as numerous S 2 multiplets originating on the 2D^o
state of the ground configuration. Weak emission from the resonance
multiplets of Cl 3 at 1011 Å and Cl 2 at 1071 Å are seen, the former
being stronger with two components roughly one-tenth the brightness
of the main components of S 3 λ 1018. Although collision strengths
for Cl ions are not readily available, the isoelectronic relationship
between S and Cl ions suggests an abundance of Cl+2 of a
few percent relative to S+, similar to the result found
by Küppers and Schneider (GRL 27, 513, 1999) for Cl+ from
optical spectra. The ratio of S 4 to S 3 brightness is about twice that
observed by HUT, which when the different slit geometries are accounted
for supports the analysis by Hall et al. (ApJ 420, L45, 1994) that S 4
emissions originate from a region more extended out of the centrifugal
plane than the S 3 emissions. We also note the detection of weak He 2
emission at 1025.3 Å, on the blue wing of geocoronal Lyman-β . The
origin of the helium ions is not clear at this time. This work is based
on data obtained for the Guaranteed Time Team by the NASA-CNES-CSA FUSE
mission operated by the Johns Hopkins University. Financial support
to U. S. participants has been provided by NASA contract NAS5-32985.

---------------------------------------------------------
Title: Far Ultraviolet Spectroscopic Explorer Observations of the
Active Cool Star AB Doradus
Authors: Ake, T. B.; Dupree, A. K.; Young, P. R.; Linsky, J. L.;
Malina, R. F.; Griffiths, N. W.; Siegmund, O. H. W.; Woodgate, B. E.
2000ApJ...538L..87A Altcode:
Far-ultraviolet spectra were obtained of the active cool star AB
Doradus (HD 36705) during the calibration and checkout period of the
Far Ultraviolet Spectroscopic Explorer (FUSE) satellite. Observations
in this early phase of the mission were taken at a resolving
power of 12,000-15,000 (~20-25 km s-1) and covered the
spectral range 905-1187 Å. The integrated spectrum exhibits strong,
rotationally broadened stellar emission from C III (λλ977, 1175)
and O VI (λλ1032, 1037) and many weaker lines. Strong emission
lines of C III and O VI exhibit broad wings. The C III λ977 profile
shows blueshifted absorption at ~30 km s-1, and C II
λ1036 absorption appears superposed on emission in the wing of O
VI λ1037. Rotational modulation of C III and O VI is present, in
harmony with its photometric variability. Flares were detected in
the brightest lines, and subexposures were analyzed to examine flux
and profile variations. Downflows that extend to 600 km s-1
during a flare are found in the O VI profiles. These early observations
demonstrate that FUSE will be an exceptional instrument for studying
chromospheres in cool stars.

---------------------------------------------------------
Title: FUSE Observations of the Active Cool Star AB Doradus
Authors: Ake, T. B.; Dupree, A. K.; Young, P. R.; Linsky, J. L.;
Malina, R. F.; Griffiths, N. W.; Siegmund, O. H. W.; Woodgate, B. E.
2000astro.ph..6117A Altcode:
Far ultraviolet spectra were obtained of the active cool star AB
Doradus (HD 36705) during the calibration and checkout period of the
FUSE satellite. Observations in this early phase of the mission were
taken at a resolving power of 12000-15000 (~20-25 km/s) and covered the
spectral range 905-1187 A. The integrated spectrum exhibits strong,
rotationally broadened stellar emission from C III (977, 1175) and O
VI (1032, 1037), and many weaker lines. Strong emission lines of C III
and O VI exhibit broad wings. The C III 977 profile shows blue-shifted
absorption at ~30 km/s and C II 1036 absorption appears superposed on
emission in the wing of O VI 1037. Rotational modulation of C III and
O VI is present, in harmony with its photometric variability. Flares
were detected in the brightest lines and subexposures were analyzed to
examine flux and profile variations. Downflows that extend to 600 km/s
during a flare are found in the O VI profiles. These early observations
demonstrate that FUSE will be an exceptional instrument for studying
chromospheres in cool stars.

---------------------------------------------------------
Title: Atomic data from the IRON Project. XL. Electron impact
excitation of the Fe XIV EUV transitions
Authors: Storey, P. J.; Mason, H. E.; Young, P. R.
2000A&AS..141..285S Altcode:
We calculate collision strengths and thermally averaged collision
strengths for electron excitation between the forty energetically
lowest levels of Fe13+. The scattering calculation is more
complete than any previous work on this ion and significant differences
are found in the excitation rates for many of the extreme ultra-violet
(EUV) transitions, compared to earlier work. A detailed comparison
is made between predicted line intensity ratios and those observed in
solar coronal spectra which shows that several outstanding discrepancies
are resolved by the new atomic data.

---------------------------------------------------------
Title: Capella: Separating the Giants
Authors: Young, P. R.; Dupree, A. K.; Gilliland, R. L.
1999AAS...195.7604Y Altcode: 1999BAAS...31.1483Y
Faint Object Camera (FOC) images from the Hubble Space Telescope
are presented showing a clean spatial separation of the two giants
in the Capella system (α Aur, HD 34029). These images were taken at
elongation (Dec. 21, 1997) when the apparent separation of the stars,
55 milliarcseconds, corresponded to 4 pixels in the FOC image. Careful
use of the objective prism mode of the FOC yielded ultraviolet spectra
with dispersion perpendicular to the axis of separation of the two
stars. The relative flux contributions to prominent UV emission
lines such as O I λ 1305, C II λ 1335 and Si IV λ 1397 can then
be derived. This direct measurement of each star's emission can be
compared to the total spectrum as obtained by STIS at a similar phase
(Sept. 12, 1999) where multiple gaussian fitting must be invoked to
separate the individual contributions. The relation of these ratios to
the known evolutionary states of the two stars, and the consequences
for theories of stellar magnetic dynamos are discussed. This research
is supported in part by an STScI Grant to SAO.

---------------------------------------------------------
Title: CHIANTI: A database for astrophysical emission line
spectroscopy
Authors: Del-Zanna, Giulio; Young, Peter; Dere, Ken; Landini, Massimo;
Landi, Enrico; Mason, Helen
1999ascl.soft11004D Altcode:
CHIANTI consists of a critically evaluated set of atomic data necessary
to calculate the emission line spectrum of astrophysical plasmas. The
data consists of atomic energy levels, atomic radiative data such as
wavelengths, weighted oscillator strengths and A values, and electron
collisional excitation rates. A set of programs that use these data to
calculate the spectrum in a desired wavelength range as a function of
temperature and density are also provided. These programs have been
written in Interactive Data Language (IDL) and descriptions of these
various programs are provided on the website.

---------------------------------------------------------
Title: Temperature and density in a polar plume - measurements
from CDS/SOHO
Authors: Young, P. R.; Klimchuk, J. A.; Mason, H. E.
1999A&A...350..286Y Altcode:
A detailed analysis of a particularly intense polar plume observed
on the 25th of October, 1996, by the Coronal Diagnostic Spectrometer
(CDS) on board the Solar and Heliospheric Observatory (SOHO) is
presented. Above the limb, emission measure distributions derived for
both the plume and a section of coronal hole background are found to
be sharply peaked at approximately 1.0-1.1 million degrees in both
regions. The temperature rises with height in the background, but no
evidence is found for a rising temperature in the plume. The density
of the background is approximately 10(8) electrons/cm(3) and falls
with height. In the plume the density is between 3.8 and 9.5x 10(8)
electrons/cm(3) , and exhibits no decrease with height up to 70 000
km. The plume base is visible on the solar surface and shows a strong
brightening lying directly below the main body of the plume. This
brightening has a temperature of 2 000 000 K, and a density of
2.5-5.6x 10(9) electrons/cm(3) . Images from lines formed at different
temperatures suggest that the morphology of the base is consistent with
an emerged bipole in a region of unipolar magnetic flux. A measurement
of the Mg/Ne relative abundance is made at two transition region
brightenings at the base of the plume. An enhancement of only 1.5 is
found over the photospheric value. Considerations of the geometry of
both the high temperature brightening at the base of the plume and
the off-limb section give filling factors of 0.5 and 1.0, respectively.

---------------------------------------------------------
Title: SunBlock '99: Young Scientists Investigate the Sun
Authors: Walsh, R. W.; Pike, C. D.; Mason, H.; Young, P.; Ireland,
J.; Galsgaard, K.
1999ESASP.446..693W Altcode: 1999soho....8..693W
SunBlock `99 is a Web-based Public Understanding of Science and
educational project which seeks to present the very latest solar
research as seen through the eyes of young British scientists. These
“solar guides” discuss not only their scientific interests, but also
their extra-curricular activities and the reasons they chose scientific
careers; in other words the human face of scientific research. The
SunBlock '99 pages gather a range of solar images and movies from
current solar space observatories and discuss the underlying physics
and its relationship to the school curriculum. The instructional level
is pitched at UK secondary school children (aged 13-16 years). It is
intended that the material should not only provide a visually appealing
introduction to the study of the Sun, but that it should help bridge
the often wide gap between classroom science lessons and the research
scientist `out in the field'. SunBlock '99 is managed by a team from
the Rutherford Appleton Laboratory and the Universities of St Andrews
and Cambridge, together with educational consultants. The production
has, in part, been sponsored by PPARC and the Millennium Mathematics
Project. Web site addresss: http://www.sunblock99.org.uk

---------------------------------------------------------
Title: Searching for Sigmoids in SOHO/CDS
Authors: Gibson, Sarah; Mason, Helen; Pike, Dave; Young, Peter
1999ESASP.446..331G Altcode: 1999soho....8..331G
Sigmoidal structures observed in X-rays have been shown to be precursors
to CMEs, existing in some cases for several days before an eruption
(Sterling and Hudson 1997,ApJ,491,L55; Canfield et al, 1999, GRL, 26,
6, 627). While these S-shaped structures are most apparent in X-ray
active region observations, they may be manifestations of a more general
helical magnetic structure having observational signatures at other
wavelengths. We will present preliminary results of a survey search for
sigmoidal structures and other CME tracers in archived SOHO/CDS data
for a series of active regions known to contain erupting sigmoidal
structures in X-ray observations. We are particularly interested in
determining the relative locations and temperatures of these tracers,
and will see to what extent the data answers questions such as,
if S shapes are observed at different wavelengths do they line up,
or is there a spatial displacement and/or rotation of angle of S that
corresponds with height/temperature variation ? How does the appearance
of the region vary over the lifetime of the observed x-ray sigmoidal
structure ? After an eruption, how much if any of the S shape remains,
and at what spatial and spectral locations ? We will use the results of
this comparison survey to consider what the implications are for the
underlying magnetic field structure, and the location and variation
of heating throughout it.

---------------------------------------------------------
Title: Electron density and temperature structure of two limb active
regions observed by SOHO-CDS
Authors: Mason, H. E.; Landi, E.; Pike, C. D.; Young, P. R.
1999SoPh..189..129M Altcode:
The analysis of two active regions on the limb using observations from
SOHO-CDS allows us to determine the electron density and temperature
distribution of the coronal emission. We find that the active regions
have hot cores (3×106 K) with larger cooler (106
K) loop structures extending above the limb. The electron number
density, determined using the Si X diagnostic line ratio, is found to
be highest in the active region core (greater than 2.3×109
cm−3). Electron number density values are determined for a
range of spectral lines from different ions and are found to increase
with temperature between 0.8 and 2.5×106 K. These results
are consistent with recent models of enhanced heating along the compact
core of active regions, where the magnetic field shear is strongest.

---------------------------------------------------------
Title: Temperature and density in coronal holes-results from CDS/SOHO
Authors: Young, Peter R.; Esser, Ruth
1999AIPC..471..273Y Altcode: 1999sowi.conf..273Y
The high speed solar wind stream comes from coronal hole regions,
and it is thought that non-plume areas may provide the dominant
contribution. Constraints on density and temperature in these regions
are extremely important for understanding the heating and acceleration
of the solar wind. Measurements are presented here from the Coronal
Diagnostic Spectrometer (CDS) on SOHO, which can resolve spectral and
spatial dimensions and so allow the study of individual features on
the solar surface.

---------------------------------------------------------
Title: CHIANTI - an atomic database for emission lines. III. Continuum
radiation and extension of the ion database
Authors: Landi, E.; Landini, M.; Dere, K. P.; Young, P. R.; Mason,
H. E.
1999A&AS..135..339L Altcode:
CHIANTI provides a database of atomic energy levels, wavelengths,
radiative transition probabilities and electron excitation data for a
large number of ions of astrophysical interest. This database allows
the calculation of theoretical line emissivities necessary for the
analysis of optically thin emission line spectra, and includes also
a suite of IDL (Interactive Data Language) programs to calculate
optically thin synthetic spectra and to perform spectral analysis and
plasma diagnostics. The first version (1.0) of the CHIANTI database was
released in 1996 te[(Dere et al. 1997)]{Der97} and has been extensively
used for analysis of line spectra from astrophysical sources by the
scientific community. The present paper describes the first major update
to the CHIANTI database which will subsequently be labeled version
2.0. The update consists of the addition of a large number of new ions,
the revision of existing data for some ions and the inclusion of an
IDL procedure to calculate the continuum. The CHIANTI atomic database
and supporting IDL routines are freely available through the internet.

---------------------------------------------------------
Title: Comparing Quiet Sun and Coronal Hole Regions with CDS/SOHO
Authors: Young, P. R.; Esser, R.
1999SSRv...87..345Y Altcode:
Spectra from the Coronal Diagnostic Spectrometer on board SOHO are
used to compare density and temperature in coronal hole and quiet
Sun regions.

---------------------------------------------------------
Title: Ellipsoidal Variations in the Soft X-Ray Transient AQL X-1
Authors: Young, P.; Welsh, W. F.; Robinson, E. L.
1998AAS...193.4308Y Altcode: 1998BAAS...30.1314Y
We have obtained 7 nights of R and I band CCD photometry of the soft
X-ray transient Aql X-1. The data were obtained in 1998 June with
the 2.1m telescope at McDonald Observatory under good conditions
(dark time, 1--2 arcsec seeing). Aql X-1 was in a quiescent state
throughout the observations. The images clearly show that a nearby,
faint star is blended with Aql X-1. The data were therefore reduced
with the point--spread function fitting routines in IRAF/DAOPHOT. We
find the amplitude of the variations to be very small. The small
amplitude of the ellipsoidal variations places a tight constraint on
the inclination of the binary system.

---------------------------------------------------------
Title: EUV Spectroscopy of Solar and Stellar Atmospheres
Authors: Young, P. R.
1998PhDT........50Y Altcode:
A variety of extreme ultraviolet (EUV) spectra from satellite and
rocket-borne instruments are studied and used both as a check on the
quality of theoretical atomic data and to determine physical parameters
for the solar atmosphere. In addition, atomic data for several ions
found in the solar atmosphere are assessed for incorporation into
the CHIANTI atomic database. For some of these ions it was necessary
to compute data using the SSTRUCT atomic code. Data from the Skylab
S082A instrument together with lines observed in the visible portion of
the solar spectrum at an eclipse are used to derive estimates of the
Ar/Ca relative abundance in the solar corona. A spectrum obtained by
the Solar Extreme ultraviolet Rocket Telescope and Spectrograph (SERTS)
is analysed thoroughly in order to check the accuracy of atomic data in
the CHIANTI atomic database, and to derive electron densities for the
observed region. Several data-sets obtained with the Coronal Diagnostic
Spectrometer (CDS) onboard the Solar and Heliospheric Observatory
(SOHO) are studied. The relative calibration of the two bandpasses of
the Normal Incidence Spectrometer of CDS is investigated by comparing
silicon and iron emission lines in different sets of spectra. Large
variations in the Mg/Ne relative abundance are found within a single
active region, and electron densities are derived. The spectra of an
intense polar plume observed by CDS are analysed and physical parameters
derived. Comparisons are made with the parameters for the coronal
hole background. EUV spectra from the stars Alpha Centauri and Procyon
obtained by the Extreme Ultra-Violet Explorer (EUVE) are presented. The
physical parameters of these two solar-like stars are then compared.

---------------------------------------------------------
Title: Atomic Physics for Atmospheric Composition Measurements
Authors: Young, P. R.; Mason, H. E.
1998SSRv...85..315Y Altcode:
The atomic physics relevant to the interpretation of solar spectra
produced by plasmas at temperatures ≳ 105 K are discussed. Methods
for determining relative abundance ratios are presented and examples
provided from the Coronal Diagnostic Spectrometer on board SOHO. In
particular, the Fe/Si ratio in the corona is found to be close to
photospheric; the Mg/Ne ratio in the transition region is found to
vary by an order of magnitude in different solar features. The Mg/Ne
ratios in supergranule cell centres and the network are separated for
the first time, although no significant differences are found.

---------------------------------------------------------
Title: Atomic Data and Spectral Line Intensities for Mg VI
Authors: Bhatia, A. K.; Young, P. R.
1998ADNDT..68..219B Altcode:
Electron collision strengths for Mg VI, calculated in the distorted-wave
approximation, are presented for all transitions between the 23 levels
of the 2s22p3, 2s2p4, 2p5,
and 2s22p23sconfigurations. Radiative data
have been calculated utilizing the same four-configuration model
of the ion. Proton rates for the transitions between the ground
states are also presented. The level balance equations for Mg VI have
been solved using these data and comparisons are made with previous
results-excellent agreement is found. Theoretical line intensities
for the important transitions are presented and compared with lines
found in the extreme ultraviolet in a spectrum from the 1989 flight
of the Solar EUV Rocket Telescope and Spectrograph. Recent data from
the Coronal Diagnostic Spectrometer onboard the Solar and Heliospheric
Observatory are also presented.

---------------------------------------------------------
Title: Giant, Repeating, Optical Bursts from the SXT Aqi X-1
Authors: Robinson, E. L.; Young, P.; Sanwal, D.
1998ASPC..137..547R Altcode: 1998wsow.conf..547R
No abstract at ADS

---------------------------------------------------------
Title: CHIANTI: an atomic database for emission lines. II. Comparison
with the SERTS-89 active region spectrum
Authors: Young, P. R.; Landi, E.; Thomas, R. J.
1998A&A...329..291Y Altcode:
The CHIANTI database was described by Dere et al. (1997, hereafter
Paper I) and the present paper applies the atomic data to the study
of extreme ultra-violet emission lines found in the SERTS-89 active
region spectrum published by Thomas &amp; Neupert (1994). Firstly,
the emission line ratios that are insensitive to density and
temperature are used to check both the quality of the atomic data and
the calibration of the instrument. Secondly, we use, where possible,
ratios that are sensitive to density to estimate the electron density
from different ions. In general we find excellent agreement between
theory and observation, providing confidence in both the atomic data
in the CHIANTI database and the quality of the SERTS-89 spectrum. Where
inconsistencies between theory and observation exist we try to explain
them in terms of either inaccuracies in the atomic data or blending of
the lines. One consistent discrepancy was that all observed lines that
we analysed in the lambr{430}{450} region were uniformly a factor of
1.5--2.0 weaker than predicted, suggesting that the SERTS-89 calibration
may need adjustment in this spectral interval. Serious problems were
also found in some of the theoretical predictions for a few ions,
especially ion{Fe}{xiv}.

---------------------------------------------------------
Title: Atomic Physics for Atmospheric Composition Measurements
Authors: Young, P. R.; Mason, H. E.
1998sce..conf..315Y Altcode:
No abstract at ADS

---------------------------------------------------------
Title: Surges and filaments in active regions during SOHO campaigns
Authors: Schmieder, B.; Deng, Y.; Rudawy, P.; Nitta, N.; Mandrini,
C. H.; Fletcher, L.; Martens, P.; Innes, D.; Young, P.; Mason, H.
1998ESASP.421..323S Altcode: 1998sjcp.conf..323S
No abstract at ADS

---------------------------------------------------------
Title: CHIANTI - an Atomic Database For Emission Lines Paper I:
Wavelengths Greater than 50 Angstroms
Authors: Dere, K. P.; Landi, E.; Mason, H. E.; Fossi, B. C. M.; Young,
P. R.
1998ASPC..143..390D Altcode: 1998sigh.conf..390D
No abstract at ADS

---------------------------------------------------------
Title: EUV spectroscopy of solar and stellar atmospheres
Authors: Young, Peter Rousselange
1998PhDT........94Y Altcode:
No abstract at ADS

---------------------------------------------------------
Title: Active Regions Observed in Extreme Ultraviolet Light by the
Coronal Diagnostic Spectrometer on SOHO
Authors: Fludra, A.; Brekke, P.; Harrison, R. A.; Mason, H. E.; Pike,
C. D.; Thompson, W. T.; Young, P. R.
1997SoPh..175..487F Altcode:
We present observations of five active regions made by the Coronal
Diagnostic Spectrometer (CDS) on the Solar and Heliospheric Observatory
(SOHO). CDS observes the Sun in the extreme ultraviolet range 150-780
Å. Examples of active region loops seen in spectral lines emitted at
various temperatures are shown. Several classes of loops are identified:
those that are seen in all temperatures up to 2 x 106 K;
loops seen at 106 K but not reaching 1.6 x 106
K; those at temperatures 2- 4 x 10-5 K and occasionally at
6 x 10-5 K but not reaching 106 K. An increasing
loop size with temperature and the relationship between the cool and
hot structures is discussed. CDS observations reveal the existence of
loops and other unresolved structures in active regions, at temperatures
between 1.5- 4 x 10-5 K, which do not have counterparts in
lines emitted above 8 x 10-5 K. Bright compact sources only
seen in the transition region lines are investigated. These sources can
have lifetimes of up to several days and are located in the vicinity
of sunspots. We study the variability of active region sources on time
scales from 30 sec to several days. We find oscillatory behaviour of Hei
and Ov line intensities in an active region on time scales of 5-10 min.

---------------------------------------------------------
Title: CHIANTI - an atomic database for emission lines
Authors: Dere, K. P.; Landi, E.; Mason, H. E.; Monsignori Fossi,
B. C.; Young, P. R.
1997A&AS..125..149D Altcode:
A comprehensive set of accurate atomic data is required for analyses of
astrophysical and solar spectra. CHIANTI provides a database of atomic
energy levels, wavelengths, radiative data and electron excitation
data for ions which are abundant in cosmic plasmas. The most recent
electron excitation data have been assessed and stored following
the method of \cite[Burgess \&amp; Tully (1992)]{bur92}. The current
version is essentially complete for specifying the emission spectrum
at wavelengths greater than 50 Angstroms. A list of observed lines in
the spectral region between 50 and 1100 Angstroms has been compiled
and compared with the lines predicted by the CHIANTI database. The
CHIANTI database reproduces the vast majority of lines observed at
these wavelengths. CHIANTI includes IDL (Interactive Data Language)
routines to calculate optically thin synthetic spectra for equilibrium
conditions. IDL routines to calculate theoretical line intensities
required for electron density or temperature diagnostics and emission
measure studies are also included. The CHIANTI atomic database and
supporting IDL routines are available by anonymous FTP.

---------------------------------------------------------
Title: The Mg/Ne abundance ratio in a recently emerged flux region
observed by CDS
Authors: Young, P. R.; Mason, H. E.
1997SoPh..175..523Y Altcode:
Evidence for the existence of the FIP-effect in the transition region is
presented here based on recent observations from the Coronal Diagnostic
Spectrometer (CDS) on-board the Solar and Heliospheric Observatory
(SOHO). Observations of an emerging flux region in lines of Mgv-vii and
Nevi-vii reveal differences in the relative Mg/Ne abundance of a factor
of 9.2 between two transition region brightenings separated by less
than 1 arc min on the Sun. The lower abundance ratio is approximately
equal to the photospheric Mg/Ne value and is associated with a small
loop-like feature in the central, hottest part of the active region. The
higher abundance ratio is found in spike-like structures at the edge
of the active region. A density diagnostic of Oiv is used to derive
an electron number density of 1011.3 cm-3 for
the low Mg/Ne brightening, while a Mgvii diagnostic gives a density
of 109.2 cm for the high Mg/Ne brightening.

---------------------------------------------------------
Title: The Tully-Fisher relation in nearby clusters
Authors: Young, P.
1997Obs...117..248Y Altcode:
No abstract at ADS

---------------------------------------------------------
Title: The Ar/Ca relative abundance in solar coronal plasma.
Authors: Young, P. R.; Mason, H. E.; Keenan, F. P.; Widing, K. G.
1997A&A...323..243Y Altcode:
The relative abundances of elements with low and high first
ionisation potentials (FIP) is a subject of much recent debate. In
situ measurements of the solar wind reveal a clear pattern of low
FIP enhancement that has been followed up with various spectroscopic
measurements of the solar corona. Argon is unique amongst the more
abundant high FIP elements in retaining several of its electrons at
the high temperatures seen in flares. This allows emission lines of
different ions to be compared with more confidence than for, say,
hydrogen-like high FIP ions such as OVIII and NeX. In this paper we
look at emission lines of the boron-like ion ArXIV; in particular,
the optical line at 4412Å, seen in eclipse observations, is compared
to the CaXIII 4086Å and CaXV 5445Å &amp; 5694Å lines to yield an
Ar/Ca abundance of 0.85+/- 0.20. In the extreme ultra-violet (EUV),
the ArXIV lines at 187.94Å and 194.41Å can be compared with CaXIV
193.87 Å - flare data from Skylab giving values of 1.10+/-0.25 and
0.55+/-0.21. Analysis of previous work indicates a photospheric Ar/Ca
abundance of 1.31+/-0.30, hence supporting the conclusion that elements
with high FIP have lower coronal abundances.

---------------------------------------------------------
Title: VizieR Online Data Catalog: CHIANTI - An Atomic Database For
Emission Lines I. (Dere+ 1997)
Authors: Dere, K. P.; Landi, E.; Mason, H. E.; Monsignori Fossi,
B. C.; Young, P. R.
1997yCat..41250149D Altcode:
A comprehensive set of accurate atomic data is required for analyses of
astrophysical and solar spectra. CHIANTI provides a database of atomic
energy levels, wavelengths, radiative data and electron excitation
data for ions which are abundant in cosmic plasmas. The most recent
electron excitation data have been assessed and stored following
the method of Burgess &amp; Tully (1992A&amp;A...254..436B). The
current version is essentially complete for specifying the emission
spectrum at wavelengths greater than 50Å. A list of observed lines
in the spectral region between 50 and 1100Å has been compiled
and compared with the lines predicted by the CHIANTI database. The
CHIANTI database reproduces the vast majority of lines observed at
these wavelengths. CHIANTI includes IDL (Interactive Data Language)
routines to calculate optically thin synthetic spectra for equilibrium
conditions. IDL routines to calculate theoretical line intensities
required for electron density or temperature diagnostics and emission
measure studies are also included. The CHIANTI atomic database and
supporting IDL routines are available by anonymous FTP. (1 data file).

---------------------------------------------------------
Title: Application of Spectroscopic Diagnostics to Early Observations
with the SOHO Coronal Diagnostic Spectrometer
Authors: Mason, H. E.; Young, P. R.; Pike, C. D.; Harrison, R. A.;
Fludra, A.; Bromage, B. J. I.; Del Zanna, G.
1997SoPh..170..143M Altcode:
The Coronal Diagnostic Spectrometer (CDS) has as a scientific goal
the determination of the physical parameters of the solar plasma
using spectroscopic diagnostic techniques. Absolute intensities and
intensity ratios of the EUV spectral emission lines can be used to
obtain information on the electron density and temperature structure,
element abundances, and dynamic nature of different features in the
solar atmosphere. To ensure that these techniques are accurate it is
necessary to interface solar analysis programs with the best available
atomic data calculations. Progress is reported on this work in relation
to CDS observations.

---------------------------------------------------------
Title: CHIANTI - an Atomic Database for Emission Line Spectroscopy:
Version 1 - Wavelengths greater than 50 Angstroms
Authors: Dere, K. P.; Monsignori-Fossi, B. C.; Landi, E.; Mason,
H. E.; Young, P. R.
1996AAS...188.8501D Altcode: 1996BAAS...28..961D
A comprehensive set of accurate atomic data is required for analyses of
astrophysical and solar spectra. CHIANTI provides an atomic database of
energy levels (wavelengths), radiative data and electron excitation data
for ions which are abundant in astrophysical plasmas. The most recent
electron excitation data have been assessed and stored following the
method of Burgess and Tully (1992). CHIANTI includes IDL (Interactive
Data Language) routines to produce optically thin synthetic spectra
for lambda &gt; 50 Angstroms, assuming equilibrium conditions. It also
includes IDL routines to calculate theoretical line intensities required
for electron density or temperature diagnostics and emission measure
studies. The CHIANTI atomic database and supporting IDL routines are
available by anonymous FTP.

---------------------------------------------------------
Title: EUV density diagnostics in solar and stellar spectra
Authors: Young, P. R.; Mason, H. E.
1996ASPC..109..301Y Altcode: 1996csss....9..301Y
No abstract at ADS

---------------------------------------------------------
Title: EUV Line Intensities of Fe X
Authors: Young, P. R.; Mason, H. E.; Bhatia, A. K.; Doschek, G. A.;
Thomas, R. J.
1996aeu..conf..583Y Altcode: 1996IAUCo.152..583Y
No abstract at ADS

---------------------------------------------------------
Title: EUV and infra-red lines of FE XIII
Authors: Young, P. R.; Mason, H. E.; Thomas, R. J.
1994ESASP.373..417Y Altcode: 1994soho....3..417Y
No abstract at ADS

---------------------------------------------------------
Title: The Effect of Low Earth Orbit Exposure on Some Experimental
Fluorine and Silicon-Containing Polymers
Authors: Connell, J. W.; Young, P. R.; Kalil, C. G.; Chang, A. C.;
Stochi, E. J.
1994NASCP3280..157C Altcode:
No abstract at ADS

---------------------------------------------------------
Title: Improved galaxy cluster distances from an optical Tully-Fisher
relation
Authors: Young, P.; Sharples, R.; Lucey, J.; Staveley-Smith, L.
1993cvf..conf..601Y Altcode:
No abstract at ADS

---------------------------------------------------------
Title: Pulsar mystery ends : the TV camera did it.
Authors: Young, P.
1990SciN..137..119Y Altcode:
No abstract at ADS

---------------------------------------------------------
Title: Why Isn't "My Discovery" News?
Authors: Young, P.
1989BAAS...21.1185Y Altcode:
No abstract at ADS

---------------------------------------------------------
Title: Spectroscopy of the Magnetic Binary Remnant of Nova V1500
Cygni 1975
Authors: Horne, K.; Schneider, D. P.; Young, P.
1987BAAS...19.1057H Altcode:
No abstract at ADS

---------------------------------------------------------
Title: High-Resolution Spectra of 24 Low-Redshift QSOs: The Properties
of MG II Absorption Systems
Authors: Tytler, David; Boksenberg, A.; Sargent, Wallace L. W.; Young,
Peter; Kunth, Daniel
1987ApJS...64..667T Altcode:
High-resolution spectra of 245 low-redshift QSOs are presented,
and Mg II emission-line equivalent widths and velocity widths are
measured and briefly discussed. Improved statistical methods are
presented for the extraction of significant absorption features from
spectra. These techniques provide a simple and accurate estimate of
the minimum equivalent widths which could be detected in any region of
a spectrum. A search for Galactic Ca II in 13 lines of sight reveals
five detections. Equivalent widths are in the range 0.2-0.3 A. Only
three redshifted absorption systems were found, all dominated by Mg
II 2796 A, 2803 A doublets. Mg(+)/Mg(0) and Mg(+)/Fe(+) values cannot
be accounted for by collisional ionization alone. Factors determining
the frequency of occurrence of Mg II systems are investigated using
a composite sample of 14 systems from the spectra of 90 QSOs. Ten out
of the 14 systems occur in five pairs of two systems each per QSO. The
probability of these pairs being chance occurrences is only 0.0007.

---------------------------------------------------------
Title: Intergalactic Lyman-alpha absorption lines in a close pair
of high-redshift QSOs.
Authors: Sargent, W. L. W.; Young, P.; Schneider, D. P.
1982ApJ...256..374S Altcode:
Spectra of Q1623+269 and Q1623+268 were obtained and these objects
were confirmed as QSO's with redshifts about 2.5. The separation of
only 2.9 arcmins corresponds at redshift 2.5 to a projected linear
separation on the plane of sky of only 1-2 Mpc. It is shown in
detail that the corresponding differential Hubble velocity over 1-2
Mpc at redshift 2.5 is about 400 km/s. Thus, a study of the redshift
distribution of the Lyman alpha absorption lines in these two objects
is capable of giving information on the clustering of the Lyman alpha
clouds on linear scales of 1-2 Mpc or velocity scales of about 400
km/s. Lists are derived of observed absorption lines for each QSO,
and the distribution of Lyman alpha lines is considered. It is shown
how cross-correlation and autocorrelation analyses of the Lyman alpha
absorption line positions may be used to study the clustering of the
clouds responsible for the lines.

---------------------------------------------------------
Title: C IV absorption in an unbiased sample of 33 QSOs: evidence
for the intervening galaxy hypothesis.
Authors: Young, P.; Sargent, W. L. W.; Boksenberg, A.
1982ApJS...48..455Y Altcode:
Observations of 27 QSOs at redshifts of z(em) approximately equals
2 with 2.5 A resolution are presented, and a homogeneous sample of
33 QSOs is prepared to examine statistical properties of C IV 1548,
1550 A absorption systems. Three QSOs out of 33 have broad absorption
troughs of material ejected by the QSO at velocities up to 0.1 c, while
in the other thirty QSOs, the C IV doublets are uniformly distributed in
the spectra in a manner consistent with predictions for clouds randomly
distributed along the line of sight in a Friedmann universe. No evidence
is found for an excess of absorption line systems in the nontroughed
QSOs near the emission redshift, and in Q1309-056 there exists strong
statistical evidence that the systems are ejected from the QSO. It
is suggested that most of the metal line absorption systems in QSOs
without broad troughs arise from the halos of intervening galaxies
and other objects unconnected with the QSOs.

---------------------------------------------------------
Title: A high-resolution study of the absorption spectra of three
QSOs: evidence for cosmological evolution in the Lyman-alpha lines.
Authors: Young, P.; Sargent, W. L. W.; Boksenberg, A.
1982ApJ...252...10Y Altcode:
High-resolution (0.8 Å FWHM) spectroscopic observations over the
wavelength range from 3260 Å to 4900 Å are presented for the QSOs
Q0002+051 (Zem = 1.899), Q0421+019 (Zem =
2.051), and the gravitationally lensed QSO, Q1115+080 (Zem
= 1.725). We find, respectively, 28, 53, and 21 absorption lines
in these three objects, from which a total of 11 absorption line
systems are identified. Two of the QSOs show galactic Ca II λλ3934,
3969 absorption. Four absorption systems with Zabs &gt;
Zem are seen in Q1115+080; the velocities range from -360
to -1130 km s-1 relative to the QSO. Line profile fits
to the absorption spectra are used to determine column densities and
velocity dispersions within the absorbing clouds. Highly ionized lines
of C IV λλ1548, 1550, N V λλ1238, 1242, and Si IV λλ1393, 1402
are seen in many of the absorption systems. The many unidentified
lines shortward of Ly emission are used to form an expanded sample of
single Lyα absorption lines. The new data provide good statistics for
Zabs &lt; 2 and reveal a number density per unit redshift
N(Z) = N0(1 + Z)γ with y = 1.81 ± 0.48. This
suggests a modest amount of cosmological evolution in the sense that
there are more Lyα absorption lines at higher redshifts. The properties
of the equivalent width spectrum of Lyα lines and the flatness of their
two-point correlation function are in accord with our previous study.

---------------------------------------------------------
Title: A high-resolution spectroscopic study of Q0119-046 and the
nature of absorption complexes with z(abs) &gt; z(em).
Authors: Sargent, W. L. W.; Young, P.; Boksenberg, A.
1982ApJ...252...54S Altcode:
In addition to finding 61 absorption lines in the QSO Q0119 through
high-resolution spectroscopic observations over the wavelength range
from 3260 to 4920 A, seven main absorption line redshifts ranging
from 0.6577 to 1.9751 are determined. A complex of three main systems
whose absolute redshift is greater than the emission redshift is found,
with infall velocities relative to the QSO ranging from -2780 to 3870
km/sec. The strongest absorption system of the complex shows C II
1334 A and excited fine structure C II 1335 A lines, implying a gas
density greater than 100/cu cm. The best of the possible explanations
for such complexes is that they arise from a cluster of galaxies,
which is perhaps collapsing, and of which the QSO is a member. The
high-velocity filaments in NGC 1275 may be similar to the clouds
responsible for the redshift systems discussed.

---------------------------------------------------------
Title: 2A 0311-227 (EF Eri) : radial velocities of two emission
line components.
Authors: Young, P.; Schneider, D. P.; Sargent, W. L. W.; Boksenberg, A.
1982ApJ...252..269Y Altcode:
The magnetic binary 2A 0311-227 is observed for more than three
orbits on each of two nights with 1 A spectral resolution and 120
s temporal resolution. The radial velocity variations of the strong
Balmer, He I, and He II emission lines in the region 4110-5050 A are
investigated. It is noted that the emission lines are distinctly from
cycle to cycle. For approximately 50% of the time, the lines consist
of a single broad component (sometimes with hints of substructure)
phased with the 81 minute orbital period. At other times, a second
'sharp' emission component appears in all lines, most notably in He
II 4686 A. The sharp component possesses an 81 minute radial velocity
period, with K equal to 600 km/s. It lags the broad component in phase
by 55 deg. Other components are seen transiently but do not reproduce
from cycle to cycle, including a high velocity component observed at
+1200 km/s. It is noted that the multiple emission components cannot
be due to magnetic effects and that the sharp component has too large
a velocity to represent orbital motion.

---------------------------------------------------------
Title: The origin of a new absorption system discovered in both
components of the double QSO Q0957+561.
Authors: Young, P.; Sargent, W. L. W.; Boksenberg, A.; Oke, J. B.
1981ApJ...249..415Y Altcode:
A new absorption-line system at z(abs) of 1.1249 has been discovered by
UV spectroscopy, at 1.2 A resolution, of the two gravitationally lensed
images of Q0957+561. The line system is visible as a C IV 1548-1550 A
doublet in both images of Q0957+561A,B, with absorption lines having
the same strengths in both images and a velocity difference of -8 +
or - 11 km/sec. The absorbing cloud velocity dispersion is less than
26 km/sec. Two interpretations are given of the observed z(em)-z(abs)
value: (1) that of an ejection, in which it corresponds to a velocity
of 37,500 km/sec, and (2) that of the result of an intervening
galaxy or intergalactic cloud, according to which it would lie at a
distance of about 300 Mpc from the QSO. It is shown that the small
velocity difference observed in the absorption lines in the two images
strengthens the ejection hypothesis for this system. It is suggested
that the discovery of multiple structure in the z(abs) 1.1249-value
system will strengthen the evidence for ejection.

---------------------------------------------------------
Title: A quest for the red companion in six cataclysmic binaries.
Authors: Young, P.; Schneider, D. P.
1981ApJ...247..960Y Altcode:
Near-infrared CCD spectra of six cataclysmic binaries have been obtained
in an attempt to detect their red dwarf components. Similar observations
of M dwarfs yield a classification scheme, based on TiO bands, which can
be used to describe the red dwarfs in cataclysmic binaries. Observations
of AM Her while in its low state revealed a red dwarf of type M4(+)
V and a distance of 80 pc. The red dwarf in DQ Her was detected in
an observation centered on mid-eclipse. The red star in DQ Her has a
spectral type of M3(+) V, a mass = 0.32 solar mass, and a radius = 0.45
solar radius. The red star in DQ Her does not lie on the main sequence;
although its temperature is correct for its mass, the radius is 25%
too large. A spectroscopic distance estimate of 400 pc to the DQ Her
binary system was obtained; in four additional systems, the red dwarf
defied detection. Lower limits to their distances are given.

---------------------------------------------------------
Title: AM Herculis : the magnetic maw uncloaks itself.
Authors: Young, P.; Schneider, D. P.; Shectman, S. A.
1981ApJ...245.1043Y Altcode:
We have obtained a complete orbit of spectroscopy at 2.3 Å resolution
on AM Herculis in its low state. We find: 1. Strong, sharp Hβ,
Hγ, and Hδ lines and weak, sharp He I λλ4471, 4922, and 5015
lines. The He II 4686 line is also weak and sharp. There is no trace of
the broad emission component present at high state. The radial velocity
amplitude K = 79 km s-1 and fiducial phase φ0 =
0.61 identify the sharp emission as being related to the sharp emission
component seen at high state. 2. The spectrum is stuffed with
broad absorption troughs flanking the Balmer lines. These troughs
are 10% deep, 80 Å wide, and vary in strength with orbital phase
(being strongest at φmag = 0.6). The troughs show internal
structure and are identified as being Zeeman-shifted multiplets of
Hβ, Hγ, and Hδ seen in a magnetic field of 1.3 × 107
gauss. The trough structure allows us to place a limit of 106 gauss
in the variation of the magnetic field in the absorption region. This
suggests the lines arise from the accreting polar cap of the white
dwarf. 3. Lower resolution (13 A) spectra in the red show strong,
narrow Hα emission. The energy distribution rises sharply longward
of 6500 Å, and there are broad, deep TiO bands from the M4.5 V red
dwarf in the binary system. The Zeeman components of Hα are confused
with some of these TiO bands.

---------------------------------------------------------
Title: The voracious vortex in HT Cassiopeiae.
Authors: Young, P.; Schneider, D. P.; Shectman, S. A.
1981ApJ...245.1035Y Altcode:
The sixteenth magnitude cataclysmic binary HT Cassiopeiae has been
observed at 2.3 Å spectral resolution and 75 s time resolution
in the region 3980-5050. Three orbits and three eclipses of this
1h46m binary have been covered. We find: (i)
strong Balmer and He I emission. The lines are double peaked, 2800
km s-1 wide, and the central absorption dip reaches down
to the continuum in He I. The K velocity of the Balmer lines is 115
km s-1. The velocity phase is offset from the eclipse by
30° and cannot be explained by the &amp;wave effect. (ii) Eclipses
of the emission lines show that mW = 0.53Msun,
mR = 0.19 Msun(q = 2.8), and α = 0.66
Rsun. The brevity of the eclipse indicates i = 76°. (iii)
The strong wings on the emission lines require a disk line emissivity
that increases toward small radii as r-3/2.

---------------------------------------------------------
Title: MV LYR : a spectroscopic study of the low state.
Authors: Schneider, D. P.; Young, P.; Shectman, S. A.
1981ApJ...245..644S Altcode:
MV Lyrae is found to have a period of 0.1336 days from radial velocity
variations. While in the low state the spectrum exhibits sharp, strong
Balmer emission and sharp, weak He I emission. The radial velocity
amplitude of the Balmer lines is 44 km/s; the He I lines have a lower
amplitude of 16 km/s. Broad, shallow Balmer absorption and He II 4686 A
absorption are also seen. Infrared observations show TiO bands and the
Na I 8183-8194 A lines; these features arise from an M5V red dwarf in
the system. The infrared spectrum combined with four-color photometry
yields a distance estimate of 320 pc to MV Lyr.

---------------------------------------------------------
Title: Q0957+561 : effects of random stars on the gravitational lens.
Authors: Young, P.
1981ApJ...244..756Y Altcode:
Computer simulations were used to study the effect of the discrete
stellar nature of the gravitational lens galaxy on the imaging of
Q0957+561. The source size of Q0957+561 is probably about 6 x 10 to the
16th cm in the optical continuum. It is predicted that all three images
will vary by 50% on a time scale of 100 years due to perturbations by
stars in the galaxy. The effect of very low mass stars in the galaxy
halo and cluster is virtually undetectable for the postulated source
size of Q0957+561 in the B1 and B2 faint images. Finally, it is found
that the observed 30% variations in the flux of Q0957+561 are unlikely
to be due to perturbations by stars.

---------------------------------------------------------
Title: The triple quasar Q1115+080A, B, C : a quintuple gravitational
lens image.
Authors: Young, P.; Deverill, R. S.; Gunn, J. E.; Westphal, J. A.;
Kristian, J.
1981ApJ...244..723Y Altcode:
Spectroscopy and direct imaging of Q1115+080A, B, C with a CCD camera
support the hypothesis that they are gravitational images of a single
object. Spectroscopy of the semiforbidden C III 1909-A emission line
shows all the images to have identical spectra and redshifts (to within
100 km/s), except that B is slightly redder. Gravitational lens imaging
by a massive spiral galaxy is investigated, and a quintuple image model
resembling Q1115+080A, B, C is found. In this model, Q1115+080A is a
highly magnified close pair of images oriented in the position angle 23
deg. An elongation Q1115+080A at this angle is seen in the CCD pictures.

---------------------------------------------------------
Title: Q0957+561 : detrailed models of the gravitational lens effect.
Authors: Young, P.; Gunn, J. E.; Kristian, J.; Oke, J. B.; Westphall,
J. A.
1981ApJ...244..736Y Altcode:
The galaxy responsible for causing multiple gravitational lens images
of QSO Q0957+561 has been reobserved spectroscopically and a more
accurate redshift of 0.36 was obtained. In addition, detailed models
of the gravitational lens effect were computed. These models, which can
explain all optical and radio data for the system, predict delays of up
to five years between variations in the A and B images (with A preceding
B). It is suggested that the third image is rather faint and located
close to the center of the lens galaxy; it is possible that this third
image contributes to the observed galaxy core. The possibility that
this system can be used to measure the Hubble constant is discussed.

---------------------------------------------------------
Title: A radial velocity study of emission in Stepanyan's star.
Authors: Young, P.; Schneider, D. P.; Shectman, S. A.
1981ApJ...244..259Y Altcode:
Emission lines in the region 4045-4945 A are observed for nearly two
complete orbits of Stepanyan's star. Three eclipses of the system
are observed at 2.5 A spectral and 100 second time resolution. The
spectral region 6800-9200 A is observed for one complete orbit at 10 A
resolution. No absorption lines or bands from a red dwarf are observed,
even at mid-eclipse. Absorption lines of O I are seen in the infrared,
which are strongest at phases 0.4-0.5 and are invisible at mid-eclipse.

---------------------------------------------------------
Title: Design of Infrared Astronomical Satellite (IRAS) primary
mirror mounts.
Authors: Schreibman, M.; Young, P.
1981OptEn..20..190S Altcode:
Abstract. The design of an operational mount to rigidly secure
the primary mirror to its baseplate without the introduction of
figure error always proves to be a major task on diffraction limited
optical systems. A summary of the design of the Infrared Astronomical
Satellite (RAS) primary mirror mount is given. The mirror was designed
to be aligned and tested at room temperature and operated in a zero
"g"field at temperatures of 2 Kbo minimize overstressing, a stiffness
requirement of greater than 150 Hz was required for cold launch and
room temperature vibration acceptance testing. Additional isolation
was required to minimize strains, introduced via the mounting base,
due to thermal and mechanical distortions.

---------------------------------------------------------
Title: Numerical models of star clusters with a central black hole. I
- Adiabatic models.
Authors: Young, P.
1980ApJ...242.1232Y Altcode:
Numerical models of star clusters containing a massive black hole are
computed for the case of a black hole which grows adiabatically in the
cluster center. The growth of the hole is assumed to be at a rate longer
than the cluster dynamical time scale but shorter than the relaxation
time scale. The angular momentum and radial action of each star in the
cluster are conserved during the adiabatic variations. This leads to the
invariance of the distribution function in (E, J) space which is used
to facilitate the numerical calculations. A power-law density cusp forms
near the black hole. When the hole has grown to exceed the core mass of
the cluster, this cusp joins smoothly onto the isothermal density law.

---------------------------------------------------------
Title: The double quasar Q0957+561 A, B: a gravitational lens image
formed by a galaxy at z=0.39.
Authors: Young, P.; Gunn, J. E.; Kristian, J.; Oke, J. B.; Westphal,
J. A.
1980ApJ...241..507Y Altcode:
Deep CCD pictures show a rich cluster of galaxies around the double
quasar Q0957 + 561 as well as faint extended wings on the image of
the southern quasar. Calculations of gravitational imaging by King
model mass distributions show that the cluster and the brightest
galaxy together, acting as a gravitational lens on the light from
a single, more distant QSO, can easily reproduce all of the present
observations. It is concluded that the double quasar is almost certainly
the multiple image of a single object produced by a gravitational lens.

---------------------------------------------------------
Title: VV Puppis and AN Ursae Majoris: a radial velocity study.
Authors: Schneider, D. P.; Young, P.
1980ApJ...240..871S Altcode:
The observations of the emission lines of VV Puppis and AN Ursae Majoris
show spectacular line variations in VV Puppis with a mean radial
velocity amplitude of 376 km/s and clearly defined broad and sharp
components. The AN UMa has similar, but less spectacular variations;
the mean radial velocity of 256 km/s and the base and emission lines
are 49 deg out of phase. Integration of particle trajectories in the
Roche geometry where a dipole magnetic field dominates the gas flow
confirms that gas is threaded on the magnetic field near the L(1)
point from which it free-falls onto the favorably oriented magnetic
pole of the white dwarf.

---------------------------------------------------------
Title: Emission line eclipse phenomena in nova DQ HER (1934).
Authors: Young, P.; Schneider, D. P.
1980ApJ...238..955Y Altcode:
H-gamma, He II 4686 A, and H-beta emission lines were observed in DQ
Her through an eclipse (phases 0.80-0.15). A total of 14 spectra with
exposure times of 300 seconds were used to investigate phenomena in
the eclispe of the emitting region by the red companion. The classical
rotational disturbance of the He II 4686 A line is observed; it changes
its velocity by over 600 km/s in 25 minutes during the eclipse. The
eclipse duration is very long (0.11 of a cycle) and indicates a mass
ratio near unity.

---------------------------------------------------------
Title: The magnetic maw of 2A 0311-22.7.
Authors: Schneider, D. P.; Young, P.
1980ApJ...238..946S Altcode:
A radial velocity study of the AM Herculis-type X-ray binary 2A 0311-227
was performed. Phase-dependent changes in profile were observed; the
line bases have K = 430 km/s and the peaks have K = 240 km/s. The peaks
have a phase lag of 25 deg relative to the bases, and the Balmer lines
exhibit drastic changes in strength through the cycle in the sense
that they are weak for large velocity displacements of the lines. It
is suggested that the emission lines may arise from material in a
magnetic funnel dropping onto the magnetic pole of a white dwarf.

---------------------------------------------------------
Title: Design of infrared astronomical satellite (IRAS) primary
mirror mounts.
Authors: Schreibman, M.; Young, P.
1980SPIE..250...50S Altcode:
The design of an operational mount to rigidly secure the primary
mirror to its baseplate without the introduction of figure error
always proves to be a major task on diffraction limited optical
systems. A summary of the design of the Infrared Astronomical Satellite
(IRAS) primary mirror mount is given. The mirror was designed to be
aligned and tested at room temperature and operated in a zero "g"
field at temperatures of 2K. To minimize overstressing, a stiffness
requirement of greater than 150 Hz was required for cold launch and
room temperature vibration acceptance testing. Additional isolation
was required to minimize strains, intro-duced via the mounting base,
due to thermal and mechanical distortions.

---------------------------------------------------------
Title: 00957+561A 00957+561B - a Gravitational Lens Image Formed by
a Galaxy at z= 0.4
Authors: Young, P.; Gunn, J.; Kristian, J.; Oke, J.; Westphal, J.
1980BAAS...12..438Y Altcode:
No abstract at ADS

---------------------------------------------------------
Title: Gravity's Lens - Squinting at a Galaxy
Authors: Walsh, D.; Carswell, R. F.; Weymann, R. J.; Burke, B. F.;
Greenfield, P. E.; Roberts, D. H.; Becklin, E. E.; Young, P.; Gunn,
J. E.; Kristian, J.; Oke, J. B.; Westphal, J. A.
1980SciN..117...36W Altcode:
No abstract at ADS

---------------------------------------------------------
Title: Alignment design for a cryogenic telescope.
Authors: Young, P.; Schreibman, M.
1980SPIE..251..171Y Altcode:
This paper describes the alignment approach for the infrared
astronomical satellite (IRAS) optical subsystem from initial design
to acceptance testing. The constraints imposed by the requirement of
maintaining alignment at 300K and 2K, in a 1-g and 0-g gravitational
field, during warm and cold vibration, and during various stages of
assembly, are discussed. The paper concludes with the methodology
of applying NASTRAN finite element analyses to the alignment design,
followed by the verification of the accuracy of the design with the
test results.

---------------------------------------------------------
Title: Improved infrared observations of AM Herculis.
Authors: Young, P.; Schneider, D. P.
1979ApJ...230..502Y Altcode:
Sharp emission lines of He I and Ca II, a broad emission line of He I,
and absorption lines of Na I have been studied in Coude spectroscopy
of AM Herculis, the prototype of a new class of X-ray binaries. The
absorption system suggests a mass function of 0.071 plus or minus 0.017
solar masses. The red dwarf appears to lie between types M4V and M5V;
according to a Roche lobe analysis, the star obeys a normal mass-radius
relationship for a lower main-sequence object. The mass of the white
dwarf cannot be determined precisely. UV irradiation of the hemisphere
of the red star which faces the white dwarf may account for the sharp
emission lines. Collisional excitation around the white dwarf may be
associated with the broad-line emission system.

---------------------------------------------------------
Title: Periodic Comet Kowal 2 (1979a)
Authors: Young, P.; Kowal, C.; Shao, C. -Y.; Bulger, J. H.; Marsden,
B. G.
1979IAUC.3346....2Y Altcode:
Further precise positions have been reported as follows: 1979 UT
R. A. (1950) Decl. m1 Observer Mar. 1.17118 4 24 56.45 + 9 28 47.1 17
Young 23.23264 5 23 54.43 + 9 45 04.2 18 Kowal 28.08417 5 36 43.12 +
9 45 09.3 Shao P. Young and C. Kowal (Hale Observatories). Measurer:
Kowal. Extremely weak and diffuse on Mar. 23. C.-Y. Shao (Harvard
College Observatory, Agassiz Station). 155-cm reflector. Measurer:
J. H. Bulger. Improved orbital elements, by the undersigned, from
11 observations Jan. 27 to Mar. 28: T = 1979 Jan. 13.740 ET Peri. =
189.380 e = 0.56380 Node = 247.163 1950.0 a = 3.48667 AU Incl. =
15.807 n = 0.151387 q = 1.52090 AU P = 6.51 years 1979 ET R. A. (1950)
Decl. Delta r m1 May 7 7 17.68 + 8 25.3 2.091 1.901 18.9 17 7 41.32 +
7 41.3 27 8 04.21 + 6 48.3 2.362 2.017 19.4 June 6 8 26.35 + 5 47.1 16
8 47.73 + 4 38.6 2.638 2.139 19.9 26 9 08.39 + 3 23.8 July 6 9 28.35 +
2 03.5 2.909 2.263 20.4

---------------------------------------------------------
Title: The Radio Galaxies NGC6251 and M87 - M87 Jet - Seyfert Galaxies
Authors: Sargent, W. L. W.; de Bruyn, A.; Readhead, A. C. S.; Young,
P.; Kristian, J.; Westphal, J.; Boksenberg, A.; Bertola, F.; Holm,
A.; Arp, H. C.; Arnold, S. J.; Sulentic, J.; Daltabuit, E.; Matthews,
K.; Morton, D. C.; Neugebauer, G.; Oke, J. B.; Persson, E.; Smith,
A. M.; Soifer, B. T.; Zimmerman, B.
1979haob.rept..754S Altcode:
No abstract at ADS

---------------------------------------------------------
Title: Dynamics of the flattened elliptical galaxy NGC 4473.
Authors: Young, P.; Sargent, W. L. W.; Boksenberg, A.; Lynds, C. R.;
Hartwick, F. D. A.
1978ApJ...222..450Y Altcode:
Spectroscopic observations of the E5 galaxy NGC 4473 to a distance of
45 sec (3300 pc) from the center along the major axis are used to make
the first estimates of the radial variation of rotation and velocity
dispersion in a galaxy away from the regions of the core. Analysis
with Fourier techniques shows the rotation curve to have an observed
semiamplitude of 60 km/s (or 86 km/s when corrected for projection). The
velocity dispersion 180 km/s is constant along the major axis of the
galaxy to a distance of 45 sec, and the line strengths fall by 35%. The
kinetic energy ratio Trot/T sub ran = 0.08 demonstrates
that the galaxy is pressure supported. The mass interior to 3.3 kpc
radius is determined to be 46 billion solar masses. The mass to light
ratio of the system is M/L = 6, and increases slowly with radius.

---------------------------------------------------------
Title: Comet Kohier (1977m)
Authors: McCutcheon, R. A.; Young, P.; Bus, S. J.; Jones, A. F.;
Marsden, B. G.
1978IAUC.3205....2M Altcode:
Further precise positions have been reported as follows: 1977/78
UT R. A. (1950) Decl. Observer Oct. 7.02847 16 42 52.05 +16 27 25.4
McCutcheon Jan. 8.13675 0 20 21.66 -34 02 10.4 Young R. A. McCutcheon
(Yale University Observatory, Bethany Station). P. Young (Palomar
Mountain Observatory). Measurer: S. J. Bus. The following elliptical
elements, by the undersigned, are based on 270 observations 1977 Sept. 6
to 1978 Jan. 30, perturbations by all nine planets being taken into
account: Epoch = 1977 Oct. 24.0 ET T = 1977 Nov. 10 5701 ET Peri. =
163.4880 e = 0.999502 Node = 181.8240 1950.0 q = 0.990570 AU Incl. =
48.7181 1978 ET R. A. (1950) Decl. Delta r m2 June 1 5 57.95 -14 28.4
3.780 3.101 17.8 11 6 13.23 -14 20.9 21 6 27.83 -14 24.7 4.059 3.327
18.3 July 1 6 41.75 -14 39.0 11 6 54.97 -15 03.3 4.298 3.548 18.7 21 7
07.45 -15 37.0 31 7 19.17 -16 19.4 4.488 3.765 19.0 Aug. 10 7 30.09 -17
09.7 20 7 40.15 -18 07.4 4.626 3.978 19.3 30 7 49.30 -19 11.6 Sept. 9
7 57.46 -20 21.5 4.711 4.188 19.6 19 8 04.54 -21 36.0 29 8 10.47 -22
54.1 4.747 4.394 19.8 Oct. 9 8 15.14 -24 14.5 19 8 18.44 -25 35.5 4.744
4.596 20.0 29 8 20.29 -26 55.2 Nov. 8 8 20.60 -28 11.4 4.718 4.795
20.2 18 8 19.33 -29 21.3 28 8 16.50 -30 22.2 4.693 4.992 20.3 Dec. 8
8 12.21 -31 11.0 18 8 06.65 -31 44.8 4.697 5.185 20.5 m2 = 10.0 + 5
log Delta + 10 log r Total visual magnitude estimates by A. F. Jones,
Nelson, New Zealand (31-cm reflector): Feb. 6.39 UT, 12.4; 8.37, 12.4.

---------------------------------------------------------
Title: 1977 VA
Authors: Helin, E.; Young, P.
1978IAUC.3158....3H Altcode:
The following precise positions have been measured by E. Helin from
exposures by P. Young with the 46-cm Schmidt at Palomar: 1977 UT
R. A. (1950) Decl. Nov. 16.26319 2 48 15.12 +13 02 40.8 17.35208 2 51
25.52 +12 55 14.6

---------------------------------------------------------
Title: Drifting continents, shifting seas.
Authors: Young, P.
1976dcss.book.....Y Altcode:
No abstract at ADS

---------------------------------------------------------
Title: Nova Cygni 1975
Authors: Fawley, W. M.; de Vaucouleurs, G.; Bryan, J.; Young, P.;
Burkhead, M. S.; Krempec, J.; Ney, E. P.; Hatfield, B.; Nissen,
W.; Jacchia, L.; di Cicco, D.; Sherrod, C.; Maley, P.; Hull, A. B.;
Woszczyk, A.; Burnicki, A.; Iwanowska, W.; Krawczyk, S.; Strobel,
A.; Hutchings, J. B.; Mannery, E.; Schommer, R.
1975IAUC.2832....1F Altcode:
W. M. Fawley, University of California at Berkeley, sends the following
re-reduced photometric observations (cf. IAUC 2830), obtained
with the Leuschner Observatory's 76-cm reflector. It is possible
that v on Aug. 30 is affected (by perhaps 0.02 magnitude) by tube
saturation. External errors in v and b-y are about 0.02. 1975 UT v b -
y u - b v - b Aug. 30.396 1.99 +0.393 +0.95 +0.36 30.521 1.95 +0.394
+1.01 +0.38 Sept. 2.185 3.95 +0.380 +0.16 +0.07 2.267 4.12 +0.349 +0.11
+0.06 2.318 4.18 +0.346 +0.11 +0.06 2.378 4.23 +0.344 +0.09 +0.05 G. de
Vaucouleurs, Department of Astronomy, University of Texas at Austin,
provides the following V magnitudes, derived from visual observations
by J. Bryan, P. Young and himself: Aug. 30.1 UT, 2.06: (4); 30.2, 2.00
(6); 30.3, 1.96 (4); 31.05, 1.91 (4); 31.1, 1.94 (3); 31.25, 1.92 (2);
Sept. 1.05, 2.07 (2); 1.1, 2.34 (2); 1.4, 2.88 (4); 2.05, 3.64 (2);
2.15, 3.63 (5); 2.4, 4.16 (4); 3.1, 4.50 (7); 3.25, 4.36 (2); 3.4,
4.57 (5); 4.1, 4.75 (6). The figures in parentheses are the number
of observations n, and the mean error is then 0.05/n**0.5. From the
exceptionally fast decay Dr. de Vaucouleurs deduces that M_v = -9.5
at maximum, and allowing for absorption of 1.0 magnitude, he derives
the nova's distance as about 1.6 kpc. M. S. Burkhead, Department of
Astronomy, Indiana University, communicates the following preliminary
photometric observations: 1975 UT V B - V U - B V - R V - I Sept. 2.131
3.61 +0.4 -0.3 +1.4 +1.8 3.116 4.41 +0.4 -0.4 +1.8 +1.9 4.227 5.02
+0.4 -0.5 +2.1 +1.8 The following photometric observations were made
by J. Krempec at the Torun Observatory: 1975 UT V B - V 1975 UT V B -
V Aug. 30.8 2.70 Sept. 2.8 3.66 +0.94 31.8 2.58 3.8 4.08 +0.99 Sept. 1.8
3.41 +0.31 E. P. Ney and B. Hatfield, University of Minnesota, report
the following magnitude observations, made on Sept. 4.0 UT: V = 5.2,
R = 3.7, I = 3.2, 2.6 at 1.2 um, 2.6 at 1.6 um, 2.1 at 2.2 um, 1.0
at 3.5 um, 0.4 at 4.8 um, -0.3 at 8.5 um, -0.5 at 10.6 um, -1.1 at
12.5 um. The following recent visual magnitude estimates have been
reported: Sept. 5.06 UT, 5.0 (W. Nissen, Arlington, Virginia); 5.06,
5.5 (L. Jacchia, Cambridge, Massachusetts); 5.07, 5.2 (D. di Cicco,
Waltham, Massachusetts); 5.07, 5.0 (C. Sherrod, North Little Rock,
Arkansas); 5.12, 4.8 (P. Maley, Houston, Texas); 6.02, 5.7 (Jacchia);
6.12, 4.9 (Maley); 7.08, 5.9 (Sherrod); 7.08, 5.2 (Maley); 8.07,
6.3 (Sherrod); 8.08, 6.1 (Jacchia); 9.06, 6.5 (Sherrod). A. B. Hull,
Flower and Cook Observatory, sends the following polarization measures,
obtained between Sept. 5.08 and 5.34 UT: at 3800 A, 1.26 percent
in p.a. 52o, 1.20 percent in 52o, 1.02 percent in 49o; at 4300 A,
1.31 percent in 47o, 1.38 percent in 47o; at 5400 A, 1.36 percent
in 46o, 1.20 percent in 46o; at 6600 A, 1.04 percent in 50o, 1.04
percent in 51o. A. Woszczyk, Torun Observatory, communicates: "A large
number of spectrograms were obtained between Aug. 29 and Sept. 4 by
A. Burnicki, W. Iwanowska, S. Krawczyk, A. Strobel and myself with
the Canadian Copernicus grating spectrograph attached to the Torun
90-cm Schmidt-Cassegrain telescope. The dispersion is 28 A/mm and the
range 3560-5050 A. On Aug. 29.884 UT there was a strong continuum and
barely visible traces of very weak and flat Balmer absorption lines
blueshifted by about 1100 km/s. The mean expansion velocity of this
absorption feature grew rapidly, reaching 1300 km/s on Aug. 30.13,
1500 km/s on Aug. 30.9, 2100 km/s on Aug. 31.9, and it stabilized at
2250 km/s between Sept. 1 and 4. The interstellar Ca II lines were
very fine and showed a velocity of about zero. Since Aug. 30 very wide
(total widths 3000 to 3400 km/s) emission lines have appeared, and their
intensities have been growing rapidly from day to day. The following
lines have been found: H-beta to H_10; Fe II 5018, 4924, 4296, 4233,
4179 A; a very large and complex emission feature centered at 4570 A
that is certainly due to Fe II 4630, 4584, 4549 and 4520 A. Fe II 4385
A is partially blended with H-gamma. Beginning on Sept. 2 the emission
lines showed a complex four-component structure that became more and
more accentuated." J. B. Hutchings, Dominion Astrophysical Observatory,
writes that spectrograms obtained on Aug. 31 and Sept. 1 (dispersions
2.5 to 15 A/mm) show broad H and Fe II emissions (+/- 2500 km/s) and
weak absorptions at -2500 and -4000 km/s. Ca II had broad absorptions
at -2000 km/s. The low-velocity absorption weakened and increased by ~
200 km/s between the two nights. E. Mannery, University of Washington,
reports that observations by R. Schommer on Sept. 4.2 UT (dispersion
60 A/mm) showed broad Balmer emission lines, each with three narrow
absorption lines superimposed.

---------------------------------------------------------
Title: Nova Sagittarii 1974.
Authors: Jones, A. F.; Mayer, E.; Morrison, P.; Young; Shanklin;
Burch; Elias, D. P.; Simmons, K.; Vidal, N.
1974IAUC.2720....1J Altcode:
No abstract at ADS

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Title: Nouveau Pas Vers La Solution du Probleme Solaire
Authors: Young
1897BSAFR..11..402Y Altcode:
No abstract at ADS

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Title: Auszug aus einem Briefe des Herrn Dr. Young, Secretair des
Board of Longitude, an den Herausgeber
Authors: Young
1822AN......1..463Y Altcode: 1823AN......1..463Y
No abstract at ADS