bernasconi

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Author name code: bernasconi
ADS astronomy entries on 2022-09-14
author:"Bernasconi, Pietro"

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Title: The Astrophysics Stratospheric Telescope for High Spectral
Resolution Observations at Submillimeter-wavelengths, ASTHROS
Authors: Pineda, Jorge; Siles, Jose; Groppi, Christopher; Kawamura,
Jonathan; Bernasconi, Pietro; Goldsmith, Paul
2022AAS...24031402P Altcode:
The Astrophysics Stratospheric Telescope for High Spectral Resolution
Observations at Submillimeter-wavelengths, ASTHROS, a 2.5-m telescope
that is planned to fly form Antarctica in 2023. The main science goal
of the mission is to obtain large scale, high spectral resolution
images of the [NII] 122um, 205um lines, to determine the electron
density structure in two star forming regions and the M83 galaxy,
which will provides important insights on the role of stellar feedback
on the regulation of star formation in galaxies. Additionally, ASTHROS
will observe the Hydrogen deuteride, HD 112um, line in a protoplanetary
disk to determine its hydrogen mass distribution. ASTHROS payload will
consists of a 4-pixel dual band cryogenic superconducting heterodyne
array camera for high-spectral resolution imaging at 1.4-1.5 THz and
2.4-2.7 THz. ASTHROS will fly for the first time a 4-K class low-power
cryocooler and thus will not require liquid helium and low power
CMOS-based spectrometers. A cryocooler will enable extended lifetime
missions, and its use will serve as a pathfinder for future NASA space
missions. In this talk I will review the science goals and technical
capabilities of the ASTHROS missio

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Title: GUSTO — The Galactic/Extragalactic Spectroscopic Terahertz
Observatory
Authors: Goldsmith, Paul; Walker, Christopher; Kulesa, Craig;
Bernasconi, Pietro; Tielens, Alexander; Wolfire, Mark; Melnick, Gary;
Hollenbach, David; Seo, Youngmin; Shipman, Russell; Neufeld, David;
Groppi, Christopher; Tolls, Volker; Young, Erick; Stark, Antony;
Yorke, Harold; Pineda, Jorge; Kawamura, Jonathan
2022AAS...24033301G Altcode:
GUSTO (Galactic/Extragalactic Spectroscopic Terahertz Observatory)
is a NASA Mission of Opportunity balloon mission currently scheduled
to be launched in December 2022 from the Long Duration Balloon
(LDB) facility near McMurdo Station, Antarctica. GUSTO will carry
out large-area observations of three key fine structure lines -
[NII] 3P1-3P0, [CII]
2P3/2-2P1/2, and [OI]
3P1-3P2, at frequencies
1461.1, 1900.5, and 4744.8 GHz, respectively. A zero pressure balloon
will support GUSTO for a baselined 75-day mission. Observing the
Southern sky from an altitude of 30-35 km, GUSTO will be above 99.99%
of atmospheric water vapor and 99.7% of the dry atmosphere. This
allows GUSTO to carry out spectral line observations essentially
unhindered by the Earth's atmosphere. Three surveys are planned - a
Galactic plane survey (GPS) covering 120o2 in the |l|&lt;
25o region, a Large Magellanic Cloud survey (LMCS) covering
25 sq. deg. in that galaxy, and targeted deep surveys (TDS) of up to
eight 1-2 sq. deg. regions. Observations of the three fine structure
lines with sub-km/s velocity resolution enables GUSTO to address key
questions about the life cycle of the ISM, including the structure of
warm neutral regions participating in and affected by star formation
(with [CII]), gas ionized by massive stars (with [NII]), and neutral
dense photon dominated regions (PDR) powered by massive young stars
(with [OI] and [CII]). GUSTO's 90 cm diameter Cassegrain telescope
provides FWHM beam widths of 0.9' - 0.6', with the 0.7' beam width at
[CII] providing spatial resolution of 2 pc at 10 kpc distance and 10 pc
at the 50 kpc distance of the LMC. The telescope is under-illuminated
at the highest frequency to yield beamwidth close to those at the lower
frequencies. The spectrometer provides velocity resolution better than
1 km/s. 3σ GPS and LMC survey sensitivities are 5-10e-6 erg/s/cm2/sr
in ~2 km/s channels at [CII] and [NII], and ~5-10e-5 erg/s/cm2/sr in ~2
km/s at [OI]. The TDS are a factor of 4 more sensitive, with sensitivity
sensing column densities corresponding to Av = 0.1 mag. The extensive
two-dimensional spectral line images of the Milky Way provided by
the GUSTO surveys will form an extensive database of the structure of
the ISM's different phases and how they connect to one another. The
extensive observations of the LMC will allow investigation of star
formation in a low-metallicity environment, and provide a template
for the ISM and star formation in dwarf galaxies and low-metallicity
distant galaxies. The TDS will permit detection of more extended neutral
and ionized gas and probe the relationship between HII regions and PDRs.

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Title: Iridium Communications Satellite Constellation Data for Study
of Earth's Magnetic Field
Authors: Anderson, Brian J.; Angappan, Regupathi; Barik, Ankit; Vines,
Sarah K.; Stanley, Sabine; Bernasconi, Pietro N.; Korth, Haje; Barnes,
Robin J.
2021GGG....2209515A Altcode:
Characterization of Earth's magnetic field is key to understanding
dynamics of the core. We assess whether Iridium Communications
magnetometer data can be used for this purpose since. The 66 Iridium
satellites are in 86° inclination, 780 km altitude, circular orbits,
with 11 satellites in each of six orbit planes. In one day the
constellation returns 300,000 measurements spanning the globe with
&lt;2° spacing. We used data from January 2010 through November 2015,
and compared against International Geomagnetic Reference Field (IGRF-11)
to inter-calibrate all data to the same model. Geomagnetically quiet
24-h intervals were selected using the total Birkeland current, auroral
electrojet, and ring current indices. The z-scores for these quantities
were combined and the quietest 16 intervals from each quarter selected
for analysis. Residuals between the data and IGRF-11 yield consistent
patterns that evolve gradually from 2010 to 2015. Residuals for each
day were binned in 9° latitude by 9° longitude and the distributions
about the mean in each bin are Gaussian with 1-sigma standard errors
of ∼3 nT. Spherical harmonic coefficients for each quiet day were
computed and time series of the coefficients used to identify artifacts
at the orbit precession (8 months) and seasonal (12 months) periods
and their harmonics which were then removed by notch filtering. This
analysis yields time series at 800 virtual geomagnetic observatories
each providing a global field map using a single day of data. The
results and CHAOS 7.4 generally agree, but systematic differences
larger than the statistical uncertainties are present that warrant
further exploration.

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Title: A Roadmap For Scientific Ballooning 2020-2030
Authors: Gorham, Peter; Walker, Christopher; Jones, William; Kierans,
Carolyn; Vieregg, Abigail; Anderson, James; Young, Eliot; Chakrabarti,
Supriya; Millan, Robyn; Bernasconi, Pietro; Guzik, T. Gregory
2019BAAS...51g.197G Altcode: 2019astro2020U.197G
The NASA Balloon Program Analysis Group (PAG) has been tasked by NASA
to develop scientific and strategic priorities for NASA's scientific
ballooning endeavors through the next decade. Here we summarize the
science priorities and draft findings and recommendations of the PAG
for the purpose of informing the Astrophysics 2020 Decadal survey.

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Title: The Far-Infrared Astronomy Stratospheric Balloon Facility
Authors: Pineda, Jorge L.; Siles, Jose V.; Kawamura, J.; Langer,
William D.; Goldsmith, Paul F.; Lis, Dariusz C.; Bernasconi, Pietro;
Groppi, Chris; Anderson, L. D.; Battersby, Cara; Looney, Leslie W.;
Cleeves, Ilse; Melnick, Gary; Smith, J. D.; Stacey, Gordon
2019BAAS...51g.177P Altcode: 2019astro2020U.177P
We recommend to the 2020 Decadal Review Committee a cost-effective
stratospheric balloon-borne facility observatory offering accommodation
interfaces for a wide range of instruments for far-infrared
astronomy. It will consist of four identical platforms featuring a
2.5-m class telescopes and will provide up to 4,000 hrs of observing
time per year.

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Title: Probing ISM Structure in Trumpler 14 and Carina I Using the
Stratospheric Terahertz Observatory 2
Authors: Seo, Young Min; Goldsmith, Paul F.; Walker, Christopher
K.; Hollenbach, David J.; Wolfire, Mark G.; Kulesa, Craig A.; Tolls,
Volker; Bernasconi, Pietro N.; Kavak, Ümit; van der Tak, Floris F. S.;
Shipman, Russ; Gao, Jian Rong; Tielens, Alexander; Burton, Michael G.;
Yorke, Harold; Young, Erick; Peters, William L.; Young, Abram; Groppi,
Christopher; Davis, Kristina; Pineda, Jorge L.; Langer, William D.;
Kawamura, Jonathan H.; Stark, Antony; Melnick, Gary; Rebolledo, David;
Wong, Graeme F.; Horiuchi, Shinji; Kuiper, Thomas B.
2019ApJ...878..120S Altcode: 2019arXiv190309517S
We present observations of the Trumpler 14/Carina I region carried out
using the Stratospheric Terahertz Observatory 2. The Trumpler 14/Carina
I region is in the western part of the Carina Nebula Complex (CNC),
which is one of the most extreme star-forming regions in the Milky
Way. We observed Trumpler 14/Carina I in the 158 μm transition of
[C II] with a spatial resolution of 48″ and a velocity resolution of
0.17 km s-1. The observations cover a 0.°25 by 0.°28 area
with central position l = 297.°34, b = -0.°60. The kinematics show
that bright [C II] structures are spatially and spectrally correlated
with the surfaces of CO clouds, tracing the photodissociation region
(PDR) and ionization front of each molecular cloud. Along seven lines of
sight (LOSs) that traverse Tr 14 into the dark ridge to the southwest,
we find that the [C II] luminosity from the H II region is 3.7 times
that from the PDR. In the same LOS, we find in the PDRs an average
ratio of 1 : 4.1 : 5.6 for the mass in atomic gas : dark CO gas :
molecular gas traced by CO. Comparing multiple gas tracers, including
H I 21 cm, [C II], CO, and radio recombination lines, we find that the
H II regions of the CNC are well described as H II regions with one
side freely expanding toward us, consistent with the Champagne model
of ionized gas evolution. The dispersal of the GMC in this region is
dominated by EUV photoevaporation; the dispersal timescale is 20-30 Myr.

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Title: Getting Ready for the Third Science Flight of SUNRISE
Authors: Barthol, Peter; Katsukawa, Yukio; Lagg, Andreas; Solanki,
Sami K.; Kubo, Masahito; Riethmueller, Tino; Martínez Pillet,
Valentin; Gandorfer, Achim; Feller, Alex; Berkefeld, . Thomas; Orozco
Suárez, David; Del Toro Iniesta, Jose Carlos; Bernasconi, Pietro;
Álvarez-Herrero, Alberto; Quintero Noda, Carlos
2018cosp...42E.215B Altcode:
SUNRISE is a balloon-borne, stratospheric solar observatory dedicated
to the investigation of the structure and dynamics of the Sun's
magnetic field and its interaction with convective plasma flows and
waves. The previous science flights of SUNRISE in 2009 and 2013 have
led to many new scientific results, so far described in around 90
refereed publications. This success has shown the huge potential of the
SUNRISE concept and the recovery of the largely intact payload offers
the opportunity for a third flight.The scientific instrumentation of
SUNRISE 3 will have extended capabilities in particular to measure
magnetic fields, plasma velocities and temperatures with increased
sensitivity and over a larger height range in the solar atmosphere, from
the convectively dominated photosphere up to the still poorly understood
chromosphere. The latter is the key interaction region between magnetic
field, waves and radiation and plays a central role in transporting
energy to the outer layers of the solar atmosphere including the
corona.SUNRISE 3 will carry 2 new grating-based spectro-polarimeters
with slit-scanning and context imaging with slitjaw cameras. The
SUNRISE UV Spectro-polarimeter and Imager (SUSI) will explore the rich
near-UV range between 300 nm and 430 nm which is poorly accessible
from the ground. The SUNRISE Chromospheric Infrared spectro-Polarimeter
(SCIP) will sample 2 spectral windows in the near-infrared, containing
many spectral lines highly sensitive to magnetic fields at different
formation heights. In addition to the two new instruments the Imaging
Magnetograph eXperiment (IMaX), an etalon-based tunable filtergraph and
spectro-polarimeter flown on both previous missions, will be upgraded
to IMaX+, enhancing its cadence and giving access to 2 spectral lines
in the visible spectral range. All three instruments will allow
investigating both the photosphere and the chromosphere and will
ideally complement each other in terms of sensitivity, height coverage
and resolution.A new gondola with a sophisticated attitude control
system including roll damping will provide improved pointing/tracking
performance. Upgraded image stabilization with higher bandwidth will
further reduce residual jitter, maximizing the quality of the science
data.SUNRISE 3 is a joint project of the German Max-Planck-Institut für
Sonnensystemforschung together with the Spanish SUNRISE consortium, the
Johns Hopkins University Applied Physics Laboratory, USA, the German
Kiepenheuer Institut für Sonnenphysik, the National Astronomical
Observatory of Japan and the Japan Aerospace eXploraion Agency (JAXA).

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Title: The GUSTO balloon mission
Authors: Bernasconi, Pietro; Walker, Christopher; Kulesa, Craig
2018cosp...42E.304B Altcode:
The Galactic/Extra-Galactic ULDB Spectroscopic Terahertz Observatory
(GUSTO) is a NASA Explorer Mission of Opportunity mission led by PI
Dr. Christopher Walker of the University of Arizona. The project goal
is to develop a Terahertz observatory and balloon-borne platform for
conducting a spectroscopic survey of the Milky Way (MW) and Large
Magellanic Cloud (LMC) to determine the composition energetics and
dynamics of the Interstellar Medium (ISM).The University of Arizona
will provide the GUSTO 0.9-m aperture telescope and instrument, which
will incorporate an array of 3x8 cryogenic Terahertz superconducting
heterodyne receivers built in a collaborative effort with the
Massachusetts Institute of Technology, Arizona State University, SRON
Netherlands Institute for Space Research, Virginia Diodes (VDI), and
Ball Aerospace. The Johns Hopkins University Applied Physics Laboratory
(JHU/APL) will provide the gondola with all its subsystems: Avionics,
Guidance and Control, and Power. JHU/APL will also provide day-to-day
project management, mission systems engineering.GUSTO will launch from
McMurdo Antarctica in December 2021 and is designed to stay aloft for
100 days or more by utilizing the 100-day flight potential of the new
Super Pressure Balloon (SPB), provided by NASA's Balloon Program Office
(BPO). During the flight the mission will measure the THz emission from
three important interstellar lines: [CII], [OI], and [NII] at 158,
63, and 205 microns, respectively, spread throughout the Milky Way
and the neighboring Large Magellanic Cloud. GUSTO will provide the
first complete study of the life cycle of the interstellar medium,
the gas and dust from which all stars and planets are formed.GUSTO
will employ a development approach that uses flight heritage from the
Stratospheric Terahertz Observatory (STO) and the Balloon Observation
Platform for Planetary Science (BOPPS) and other prior balloon missions.

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Title: Stratospheric balloon observations of comets C/2013 A1
(Siding Spring), C/2014 E2 (Jacques), and Ceres
Authors: Cheng, Andrew F.; Hibbitts, C. A.; Espiritu, R.; McMichael,
R.; Fletcher, Z.; Bernasconi, P.; Adams, J. D.; Lisse, C. M.; Sitko,
M. L.; Fernandes, R.; Young, E. F.; Kremic, T.
2017Icar..281..404C Altcode:
The Balloon Observation Platform for Planetary Science (BOPPS)
was launched from Fort Sumner, New Mexico on September 26, 2014 and
observed Oort Cloud comets from a stratospheric balloon observatory,
using a 0.8 meter aperture telescope, a pointing system that achieved
&lt; 1 arc second pointing stability, and an imaging instrument suite
covering the near-ultraviolet to mid-infrared. BOPPS observed two Oort
Cloud comets, C/2013 A1 (Siding Spring) and C/2014 E2 (Jacques), at
the 2.7 μm wavelength of water emission. BOPPS also observed Ceres at
2.7 μm wavelength to characterize the nature of hydrated materials on
Ceres. Absolute flux calibrations were made using observations of A0V
stars at nearly the same elevations as each target. The Comet Siding
Spring brightness in R-band was magnitude R = 10.8 in a photometric
aperture of 17.4″. The inferred H2O production rate from
Comet Siding Spring was 6 × 1027 s-1, assuming
optically thin emissions, which may be a lower limit if optical depth
effects are important. A superheat dust population was discovered at
Comet Jacques, producing a bright infrared continuum without evidence
for line emission. Observations of Ceres from BOPPS and from IRTF,
obtained the same night, did not find evidence for a strong water
vapor emission near 2.7 μm and led to an approximate upper limit &lt;
7 × 1027 s-1 for water emission from Ceres.

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Title: Optical design for the large balloon reflector
Authors: Cortes-Medellin, German; O'Dougherty, Stefan; Walker,
Christopher; Goldsmith, Paul F.; Groppi, Chris; Smith, Steve;
Bernasconi, Pietro
2016SPIE.9906E..1YC Altcode:
We present the details of the optical design, corrector system,
mechanical layout, tolerances, pointing requirements, and overall
performance of the sub-millimeter wavelength Large Balloon Reflector
telescope (LBR).

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Title: the APL Balloonborne High Altitude Research Platform (HARP)
Authors: Adams, D.; Arnold, S.; Bernasconi, P.
2015ESASP.730..393A Altcode:
The Johns Hopkins University Applied Physics Laboratory (APL) has
developed and demonstrated a multi-purpose stratospheric balloonborne
gondola known as the High Altitude Research Platform (HARP). HARP
provides the power, mechanical supports, thermal control, and data
transmission for multiple forms of high-altitude scientific research
equipment. The platform has been used for astronomy, cosmology and
heliophysics experiments but can also be applied to atmospheric studies,
space weather and other forms of high altitude research. HARP has
executed five missions. The first was Flare Genesis from Antarctica
in 1993 and the most recent was the Balloon Observation Platform for
Planetary Science (BOPPS) from New Mexico in 2014. HARP will next
be used to perform again the Stratospheric Terahertz Observatory
mission, a mission that it first performed in 2009. The structure,
composed of an aluminum framework is designed for easy transport
and field assembly while providing ready access to the payload and
supporting avionics. A light-weighted structure, capable of supporting
Ultra-Long Duration Balloon (ULDB) flights that can last more than 100
days is available. Scientific research payloads as heavy as 600 kg
(1322 pounds) and requiring up to 800 Watts electrical power can be
supported. The platform comprises all subsystems required to support
and operate the science payload, including both line-of-sight (LOS)
and over-the-horizon (0TH) telecommunications, the latter provided
by Iridium Pilot. Electrical power is produced by solar panels for
multi-day missions and batteries for single-day missions. The avionics
design is primarily single-string; however, use of ruggedized industrial
components provides high reliability. The avionics features a Command
and Control (C&amp;C) computer and a Pointing Control System (PCS)
computer housed within a common unpressurized unit. The avionics
operates from ground pressure to 2 Torr and over a temperature range
from —30 C to +85 C. Science data is stored on-board and also flows
through the C&amp;C computer where it is packetized for real-time
downlink. The telecommunications system is capable of LOS downlink
up to 3000 kbps and 0TH downlink up to 120 kbps. The pointing control
system (PCS) provides three-axis attitude stability to 1 arcsec and can
be used to aim at a fixed point for science observations, to perform
science scans, and to track an object ephemeris. This paper provides
a description of HARP, summarizes its performance on prior flights,
describes its use on upcoming missions and outlines the characteristics
that can be customized to meet the needs of the high altitude research
community to support future missions.

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Title: Stratospheric Infra-Red Imaging and Spectroscopy for Planetary
Science (SIRIS-PS)
Authors: Hibbitts, C. A.; Kremic, T.; Cheng, A.; Bernasconi, P.;
Rivkin, A.
2015LPI....46.2152H Altcode: 2015LPICo1832.2152H
This infrared imaging and spectroscopy mission would conduct unique
and valuable Decadal science at relatively low cost with a brief
development period.

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Title: BOPPS Rapid Response Planetary Science: First Results
Authors: Cheng, A. F.; Hibbitts, C. A.; Bernasconi, P.; Young, E. F.
2015LPI....46.1409C Altcode: 2015LPICo1832.1409C
The first images of comets from a stratospheric balloon observatory
have been obtained by the Balloon Observation Platform for Planetary
Science (BOPPS) mission.

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Title: STO-2: Support for 4th Year Operations, Recovery, and Science
JHU/APL Co-I
Authors: Bernasconi, Pietro
2015apra.prop...28B Altcode:
This is a collaboration Co-I Institution proposal for the proposal
"STO-2: Support for 4th Year Operations, Recovery, and Science"
whose lead proposal is submitted by the University of Arizona
with Dr. Christofer Walker as PI. STO-2 was flight-ready in the
2015-2016 austral summer. However, due to the late establishment of the
stratospheric anti-cyclone and poor surface conditions, STO-2 was unable
to launch. The decision was made to winter-over the STO-2 payload in
its hangar for launch during the 2016-2017 Antarctic campaign. Funds to
cover preparations and deployment of key members of the instrument team
in support of the campaign are being provided by NASA under the existing
grant. However, these funds are only sufficient to cover expenses up
to approximately December 31st. Here we request supplemental funds
to cover costs associated with STO-2 operations and recovery beyond
this date. STO-2 will address a key problem in modern astrophysics,
understanding the Life Cycle of the Interstellar Medium (ISM). STO-2
will survey approximately 1/4 of the Southern Galactic Plane in the
dominant interstellar cooling line [CII] (158 μm) and the important
star formation tracer [NII] (205 μm). In addition, STO-2 will perform
path finding observations of the 63 μm [OI] line toward selected
regions. With 1 arcminute angular resolution, STO-2 will spatially
resolve atomic, ionic and molecular clouds out to 10 kpc. The STO-2
survey will be conducted at unparalleled sensitivity levels. STO-2 will
uniquely probe the pivotal formative and disruptive stages in the life
cycle of interstellar clouds and the relationship between global star
formation rates and the properties of the ISM. Combined with previous HI
and CO surveys, STO-2 will create 3-dimensional maps of the structure,
dynamics, turbulence, energy balance, and pressure of the Milky Way's
ISM, as well as the star formation rate. Once we gain an understanding
of the relationship between ISM properties and star formation in the
Milky Way, we can better interpret observations of nearby galaxies
and the distant universe. The mission goals for these surveys are to:
1) Determine the life cycle of Galactic interstellar gas. 2) Study
the creation and disruption of star-forming clouds in the Galaxy. 3)
Determine the parameters that affect the star formation rate in the
galaxy. 4) Provide templates for star formation and stellar/interstellar
feedback in other galaxies. STO-2 reuses the 80 cm telescope and many
subsystems from STO-1. It also reuses the gondola developed by APL for
the BOPPS and BRISSON comet missions. For the STO- 2 flight, STO-1's
high spectral resolution (&lt;1 km/s) heterodyne receiver system was
upgraded for extended cryogenic lifetime, enhanced sensitivity, and
greater reliability. The flight receiver has five, cryogenic HEB mixers;
two optimized for the 158 μm [CII] line, two for the 205 μm [NII]
line, and one for the 63 μm [OI] line. STO is capable of detecting
every giant molecular cloud, every HII region of significance, and
every diffuse HI cloud with (AV &gt;= 0.4) within its survey region.

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Title: BOPPS Observations of Oort Cloud Comets Siding and PanSTARRS
Authors: Cheng, A. F.; Hibbitts, C.; Young, E. F.; Bernasconi, P. N.;
Tibor, K.
2014AGUFM.P42A..04C Altcode:
The Balloon Observation Platform for Planetary Science (BOPPS)
mission is a stratospheric balloon mission to conduct planetary
science observations during a one-day flight from Ft. Sumner, NM
in late September, 2014. BOPPS will fly an 80-cm telescope with two
instruments to detect and characterize two Oort Cloud comets, C/2013
A1 Siding Spring and C/2012 K1 PanSTARRS. The BOPPS instruments [1,2]
are the BOPPS Infrared Camera (BIRC), imaging at R band and from 2.5
to 5 microns, and the UVvis camera which includes a fine pointing
system to demonstrate sub-arc second pointing and ability to obtain
high SNR imaging at wavelengths near 300 nm sensitive to OH emission
(1). The BIRC will image the comets in nine filter pass bands at 1.16
arc second per pixel resolution and will measure the strengths of H2O
and CO2 emissions at 2.7μ and 4.3μ respectively. These are the primary
volatiles driving cometary activity, and there is no alternative way to
make these measurements from Earth or from space. The BIRC observations
of Comet Siding Spring will occur about three weeks prior to the close
approach of the comet to Mars, which will also be observed by the
full constellation of Mars spacecraft. We will report initial results
of BOPPS comet observations. References: [1] Young EF et al. (2014),
Fall AGU this session [2] Hibbitts et al., (2014), Fall AGU

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Title: Brrison IR Camera (birc)
Authors: McMichael, R. T.; Noble, M. W.; Adams, D.; Bernasconi,
P.; Borowski, H.; Bupp, R.; Cheng, A. F.; Eaton, H.; Espiritu, R.;
Fletcher, Z.; Heffernan, K.; Hibbitts, K.; Kee, C. L.; Maahs, G.;
Murphy, G.; Ponnusamy, D.; Rolander, N. W.; Strohbehn, K.; Troll,
J. R.; Williams, B. D.
2014SPIE.9145E..2WM Altcode:
BIRC is a multispectral infrared imager designed to operate in 8
bandpasses between 2.5 and 5.0 μm utilizing a cryocooled HgCdTe
detector and Ø80 cm telescope. The instrument was flown on a
ballooncraft platform and operated in a near-space environment. BIRC
was designed to measure the water and CO2 emissions from
the comet ISON. The system produces an f/4 image over a field of view
of 3 arcminutes, and employs shift/co-add algorithms to observe dim
objects. An innovative thermal design holds the system components
in separate vacuum and atmospheric zones which are independent of
the neighboring instrument deck. This paper summarizes the design,
test and integration of the BIRC instrument.

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Title: A Comparative Evaluation of Automated Solar Filament Detection
Authors: Schuh, M. A.; Banda, J. M.; Bernasconi, P. N.; Angryk, R. A.;
Martens, P. C. H.
2014SoPh..289.2503S Altcode: 2014SoPh..tmp...34S
We present a comparative evaluation for automated filament detection
in Hα solar images. By using metadata produced by the Advanced
Automated Filament Detection and Characterization Code (AAFDCC)
module, we adapted our trainable feature recognition (TFR) module to
accurately detect regions in solar images containing filaments. We
first analyze the AAFDCC module's metadata and then transform it into
labeled datasets for machine-learning classification. Visualizations
of data transformations and classification results are presented and
accompanied by statistical findings. Our results confirm the reliable
event reporting of the AAFDCC module and establishes our TFR module's
ability to effectively detect solar filaments in Hα solar images.

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Title: BRRISON Mission Overview (Invited)
Authors: Cheng, A. F.; Hibbitts, C.; Bernasconi, P. N.; Young, E. F.;
Tibor, K.; Arnold, S. P.; Adams, D.
2013AGUFM.P31A1791C Altcode:
The Balloon Rapid Response for ISON (BRRISON) mission will make balloon
observations of Comet C/2012S1 ISON prior to the comet's perihelion on
Nov. 28, 2013. Comet ISON is a sun-grazing comet, which has freshly
emerged from the Oort Cloud and may not survive intact its plunge
through the solar atmosphere. BRRISON will make unique observations of
CO2 and H20 emissions in the fundamental vibrational bands of these most
important cometary volatiles. The BRRISON stratospheric balloon-borne
platform will launch from Fort Sumner, NM on a one-day flight, with
the launch window opening September 17, 2013. The science payload
consists of two instruments, the BRRISON IR Camera (BIRC) supplied by
The Johns Hopkins Applied Physics Laboratory for imaging in the 2.5
micron to 5 micron range, and the UVVis near-ultraviolet and visible
camera imager supplied by the Southwest Research Institute. The UVVis
Imager includes a fast steering mirror and fine pointing system. BRRISON
plans to observe, in addition to the Oort Cloud comet ISON, the evolved
Jupiter Family Comet 2/P Encke to compare the CO2 and H20 emissions of
these end-members of the comet population. In addition, BRRISON plans
to observe the Jupiter system, the Moon, hydrated main belt asteroids,
and the bright, multiple star systems Castor and Mizar for calibration
and for demonstration of the fine pointing system. I will present an
overview of the BRRISON mission and its initial results.

---------------------------------------------------------
Title: BRISSON Mid-IR Observations of the Moon and Galilean Satellites
Authors: Hibbitts, C.; Cheng, A. F.; Heffernan, K.; Bernasconi, P. N.;
Young, E. F.
2013AGUFM.P43A2010H Altcode:
The NASA BRRISON mission is performing observations of the Moon, Io,
Callisto, as well as Jupiter, several asteroids, and comet Encke
in addition to its primary target of comet ISON (1). The BRRISON
mission will observe these secondary targets with its multispectral
mid-infrared camera that is equipped with an astronomical R-band filter
and an additional 8 filters, ranging from 2.5 microns to 4.6 microns,
selected to characterize the peak and continuua of the CO2 and water
emission bands from comet ISON (and Encke). These bands are also well
positioned to characterize the hydroxyl/water absorption band in
sunlight reflected from the surfaces of the Moon (2,3,4) and other
airless bodies, as well as provide a multiple component temperature
measurement of the thermal emission from them. The OH-related absorption
bands on the Moon have already been characterized and mapped over the
equatorial and mid-latitudes of the Moon (2,5), but at higher latitudes
the band shape changes, broadening and possibly shifting to longer
wavelengths. The later would be indicative of H2O. The multispectral
capability of the IR instrument enables the BRRISON mission to determine
if the molecule responsible for the 3-micron absorption band on the Moon
can be attributed to H2O or if it is consistently and only OH, including
mapping the distribution, depths, and shapes of the 3-micron band(s)
over a significant portion of the Moon's nearside surface. Additionally,
a possible change in OH- abundance with illumination/temperature has
been observed by at least one of the three discovery spacecraft (2),
but has not be further characterized by additional measurements. Because
the BRRISON mission is planning to image a significant portion of the
lunar surface, the multispectral measurements will be able to address
that question as well. Third, surface temperatures will be calculated
for the same pixels to enable exploring correlations between surface
temperature and the 3-micron band characteristics. Surface temperatures
will also be measured for other airless bodies, including the only
non-icy Galilean satellite - Io. Additionally, the depth of the CO2
absorption feature on Callisto will be measured, to be compared with
similar observations from Galileo NIMS and especially Cassini VIMS
(6), which also obtained slightly subpixel observations of Callisto
during its flyby of the Jovian system at the end of year 2000. (1)
Cheng et al., AGU, 2013. (2) Pieters et al., Science, DOI: 10.1126
/science 1178658, 2009; (3) Sunshine et al., 10.1126/science.1179788,
2009; (4) Clark, R.N., 10.1126/science.1178105, 2009/; (5) McCord et
al., JGR-Planets, VOL. 116, E00G05, doi:10.1029/2010JE003711, 2011;
(6) McCord et al., Icarus 172 (2004) 104-126, 2013.

---------------------------------------------------------
Title: Towards the next HST: Fine Guiding Results from the BRRISON
Mission
Authors: Young, E. F.; Osterman, S. N.; Cheng, A. F.; Hibbitts, C.;
Bernasconi, P. N.
2013AGUFM.P31A1785Y Altcode:
The Balloon Rapid Response for ISON (BRRISON) mission is expected to
make observations from altitudes near 125,000 ft (35 km, above 99.5%
of the atmosphere) for several hours. Previous balloon missions have
provided quantitative evidence that wavefront errors are negligible
from this altitude. In order to take advantage of the space-like
seeing conditions in the stratosphere, a balloon-borne telescope
should be stabilized at a level that is comparable to the telescope's
diffraction limit. The stabilization problem consists of two separate
tasks: measuring the time-varying pointing error signal and correcting
those pointing errors. BRRISON is equiped with coarse and fine pointing
systems: a pair of star trackers and an IMU to control the elevation and
azimuth pointing of the telescope and a high-speed sCMOS guide camera
and a fine steering mirror to compensate for finer image motion. We
will report on the precision and bandwidth of the pointing error
signal and of the fine steering mirror's corrections. Expected targets
include Jupiter and Comets Encke and ISON, in filters inherited from
the Hale-Bopp campaign to isolate OH (310 nm) and CN (385 nm) features.

---------------------------------------------------------
Title: BRRISON Observations of Comet ISON
Authors: Cheng, A. F.; Hibbitts, C.; Young, E. F.; Heffernan, K.;
Bernasconi, P. N.
2013AGUFM.P24A..05C Altcode:
The BRRISON mission will fly a stratospheric balloon-borne platform
from Fort Sumner, NM to measure CO2 and H20 emissions at 4.3 micron
and 2.7 micron, respectively from Comet ISON. If the flight duration
reaches at least 18 hours, which will depend on upper level wind
conditions, BRRISON will observe both ISON and the Jupiter Family comet
2P/Encke. BRRISON will carry a near-IR camera imaging in 8 near-IR
filter passbands between 2.5 and 5 microns, with an additional filter
for imaging in R band. ISON is an Oort Cloud comet, which preserves
icy materials which have never been heated by passage through the
inner solar system. As an Oort Cloud comet, it may have formed from
different materials and under different conditions than Kuiper Belt
comets, and particularly the Jupiter Family comets whose orbits have
evolved to make repeated passes through the inner solar system. Comet
Encke is a highly evolved member of the latter population with a
perihelion of only 0.33 AU, inside the orbit of Mercury. Comparing
the compositions of the Oort Cloud comet ISON, versus the evolved
Kuiper Belt comet Encke, will help us to understand diverse cometary
origins and dynamical histories. BRRISON observations may also help
us understand whether and how comets formed in different regions of
the early solar system may differ, and how key volatiles, including
water and CO2, were distributed in the solar nebula. I will present
initial results of BRRISON comet observations.

---------------------------------------------------------
Title: Plasma Disturbances in the Solar Polar Regions
Authors: Raouafi, N.; Bernasconi, P. N.
2012AGUFMSH53A2269R Altcode:
We investigate ubiquitous transient brightenings in coronal open
structures seen with SDO/AIA and STEREO/SECCHI. EUV observations near
the solar surface show that polar plumes (and also inter-plume regions)
have been observed to harbor small outward-moving fluctuations in
brightness on time scales of several minutes. It is not clear whether
the fluctuations comprise boluses of material moving outward, wave
phenomena, or both. The anti-sunward propagating blobs have velocities
ranging from a few 10 km/sec to more than 100 km/sec.

---------------------------------------------------------
Title: Micro-Sigmoids as Progenitors of Polar Coronal Jets
Authors: Raouafi, N. -E.; Bernasconi, P. N.; Rust, D. M.; Georgoulis,
M. K.
2012ASPC..454..299R Altcode:
Observations from the Hinode X-ray telescope (XRT) are used to study
the structure of X-ray bright points (XBPs), sources of coronal
jets. Several jet events are found to erupt from S-shaped bright
points, suggesting that coronal micro-sigmoids are progenitors of the
jets. The observations may help to explain numerous characteristics
of coronal jets, such as helical structures and shapes. They also
suggest that solar activity may be self-similar within a wide range
of scales in terms of both properties and evolution of the observed
coronal structures.

---------------------------------------------------------
Title: Solar Bolometric Imager for Investigating the Sources of
Solar Irradiance Variability
Authors: Bernasconi, Pietro N.; Foukal, P. V.
2012AAS...22020114B Altcode:
The Solar Bolometric Imager is an innovative instrument for the
investigation of the sources of solar irradiance variability. It
makes precise, wavelength-integrated, photometric measurements of
the irradiance variations originating in the solar photosphere. It
provides images with spectrally flat response over the range 200-2600
nm, which includes about 95% of the total solar irradiance (TSI). It
is important to realize that the SBI measures broad band contrast
of thermal structures relative to their surroundings, so it does not
require absolute accuracy or even high long term reproducibility. Its
angular resolution (1 arcsecs/pixel) and field of view (320x240
arcsecs) are optimized to discriminate between TSI contributions from
different magnetic and non-magnetic solar regions. The detector is an
uncooled bolometric array with 320x240 ferro-electric pixels, coated
with gold-black to achieve uniform sensitivity at all wavelengths of
incident light. We are in the process of developing a space based
SBI that builds upon the heritage of a stratospheric balloon-borne
instrument successfully flown in 2003, and 2007. A space-based SBI
will directly attack one of the most challenging problems in solar
research: “What are the origins of long term solar total output
variation on centennial and millennial time scales?” In addition,
SBI measurements will continue to increase our understanding of solar
magneto-convection, and more generally the underlying physics of
solar magnetic variability. Here we present the results of our
latest instrument development efforts aimed at bringing the current
SBI prototype to a Technology Readiness Level suitable for a SMEX or
a Mission of Opportunity.

---------------------------------------------------------
Title: A Comparative Evaluation of Automated Solar Filament Detection
Authors: Schuh, Michael; Banda, J.; Bernasconi, P.; Angryk, R.;
Martens, P.
2012AAS...22020105S Altcode:
We present a comparative evaluation for automated filament detection
in H-alpha solar images. By using metadata produced by the Advanced
Automated Filament Detection and Characterization Code (AAFDCC)
module, we adapted our Trainable Feature Recognition (TFR) component
to accurately detect regions in solar images containing filaments. We
first analyze the module's metadata and then transform it into
labeled datasets for machine learning classification. Visualizations
of data transformations and classification results are presented
and accompanied by statistical findings. Our results confirm the
reliable event reporting of the AAFDCC module as well as our ability
to effectively detect solar filaments with our TFR component.

---------------------------------------------------------
Title: Plasma Blobs in the Solar Polar Regions: Outflows or Waves?
Authors: Raouafi, Nour-Eddine; Bernasconi, P. N.; Georgoulis, M. K.
2012AAS...22020104R Altcode:
We analyze EUV images from the Solar Dynamic Observatory
(SDO). Anti-sunward propagating blob are found almost everywhere within
the solar polar regions with velocities ranging from a few 10 km s-1
to more than 100 km s-1. These structures are either flows or waves. In
the former case they may reflect the structure of the nascent fast solar
wind. The case is also important for the heating of the coronal plasma.

---------------------------------------------------------
Title: Computer Vision for the Solar Dynamics Observatory (SDO)
Authors: Martens, P. C. H.; Attrill, G. D. R.; Davey, A. R.; Engell,
A.; Farid, S.; Grigis, P. C.; Kasper, J.; Korreck, K.; Saar, S. H.;
Savcheva, A.; Su, Y.; Testa, P.; Wills-Davey, M.; Bernasconi, P. N.;
Raouafi, N. -E.; Delouille, V. A.; Hochedez, J. F.; Cirtain, J. W.;
DeForest, C. E.; Angryk, R. A.; De Moortel, I.; Wiegelmann, T.;
Georgoulis, M. K.; McAteer, R. T. J.; Timmons, R. P.
2012SoPh..275...79M Altcode: 2011SoPh..tmp..144M; 2011SoPh..tmp..213M; 2011SoPh..tmp....8M
In Fall 2008 NASA selected a large international consortium to produce
a comprehensive automated feature-recognition system for the Solar
Dynamics Observatory (SDO). The SDO data that we consider are all of the
Atmospheric Imaging Assembly (AIA) images plus surface magnetic-field
images from the Helioseismic and Magnetic Imager (HMI). We produce
robust, very efficient, professionally coded software modules that
can keep up with the SDO data stream and detect, trace, and analyze
numerous phenomena, including flares, sigmoids, filaments, coronal
dimmings, polarity inversion lines, sunspots, X-ray bright points,
active regions, coronal holes, EIT waves, coronal mass ejections
(CMEs), coronal oscillations, and jets. We also track the emergence and
evolution of magnetic elements down to the smallest detectable features
and will provide at least four full-disk, nonlinear, force-free magnetic
field extrapolations per day. The detection of CMEs and filaments is
accomplished with Solar and Heliospheric Observatory (SOHO)/Large
Angle and Spectrometric Coronagraph (LASCO) and ground-based Hα
data, respectively. A completely new software element is a trainable
feature-detection module based on a generalized image-classification
algorithm. Such a trainable module can be used to find features that
have not yet been discovered (as, for example, sigmoids were in the
pre-Yohkoh era). Our codes will produce entries in the Heliophysics
Events Knowledgebase (HEK) as well as produce complete catalogs for
results that are too numerous for inclusion in the HEK, such as the
X-ray bright-point metadata. This will permit users to locate data on
individual events as well as carry out statistical studies on large
numbers of events, using the interface provided by the Virtual Solar
Observatory. The operations concept for our computer vision system is
that the data will be analyzed in near real time as soon as they arrive
at the SDO Joint Science Operations Center and have undergone basic
processing. This will allow the system to produce timely space-weather
alerts and to guide the selection and production of quicklook images and
movies, in addition to its prime mission of enabling solar science. We
briefly describe the complex and unique data-processing pipeline,
consisting of the hardware and control software required to handle
the SDO data stream and accommodate the computer-vision modules, which
has been set up at the Lockheed-Martin Space Astrophysics Laboratory
(LMSAL), with an identical copy at the Smithsonian Astrophysical
Observatory (SAO).

---------------------------------------------------------
Title: Reflight of the Stratospheric TeraHertz Observatory: STO-2
Authors: Bernasconi, Pietro
2012apra.prop...98B Altcode:
This is the Lead Proposal for the "Reflight of the Stratospheric
TeraHertz Observatory: STO-2". STO-2 will address a key problem in
modern astrophysics, understanding the Life Cycle of the Interstellar
Medium (ISM). STO-2 will survey approximately 1/4 of the Southern
Galactic plane in the dominant interstellar cooling line [CII] (158
μm) and the important star formation tracer [NII] (205 μm). With ~1
arcminute angular resolution, STO-2 will spatially resolve atomic,
ionic and molecular clouds out to 10 kpc. Taking advantage of its
enhanced, extended lifetime cryogenic receivers, the STO-2 survey will
be conducted at unparalleled sensitivity levels. STO- 2 will uniquely
probe the pivotal formative and disruptive stages in the life cycle of
interstellar clouds and the relationship between global star formation
rates and the properties of the ISM. Combined with previous HI and
CO surveys, STO-2 will create 3-dimensional maps of the structure,
dynamics, turbulence, energy balance, and pressure of the Milky Way's
ISM, as well as the star formation rate. Once we gain an understanding
of the relationship between ISM properties and star formation in the
Milky Way, we can better interpret observations of nearby galaxies
and the distant universe. The mission goals for these surveys are
to: 1) Determine the life cycle of Galactic interstellar gas, 2)
Study the creation and disruption of star-forming clouds in the
Galaxy, 3) Determine the parameters that affect the star formation
rate in the galaxy, and 4) Provide templates for star formation
and stellar/interstellar feedback in other galaxies. STO-2 will
re-use the 80cm telescope, gondola, and subsystems from STO-1. For
the STO-2 flight, STO-1 s high spectral resolution (&lt;1 km/s)
heterodyne receiver system will be upgraded for extended cryogenic
lifetime, enhanced sensitivity, and greater reliability. The flight
receiver has eight, cryogenic HEB mixers; four optimized for the [CII]
line and four for the [NII] line. STO-2 will also fly an uncooled,
Schottky receiver to observe the 609 μm [CI] line at 3 arcminute
resolution. The instrument spectrometer has sufficient bandwidth to
detect all clouds participating in Galactic rotation in each of its
9 pixels. STO is capable of detecting every giant molecular cloud,
every HII region of significance, and every diffuse HI cloud with (AV
e 0.4) within its survey region. The STO-1 launch was on 15 January
2012. Before achieving float altitude a frozen absolute pressure
regulator vented approximately half of the liquid helium supply to
the atmosphere. This event reduced the cryogenic (THz) portion of the
mission to ~5 days. The efficacy of the observations conducted during
this period was hindered by several technical issues experienced
early in the flight. The causes of these issues were identified and
corrected in flight. STO then transitioned into its `Warm Mission
science program and continued observations using an uncooled 492 GHz
[CI] receiver until the end of its flight on 29 January 2012. Here we
propose to re-fly STO with an upgraded, more robust cryogenic/receiver
system that will allow THz observations to continue until stratospheric
conditions or recovery constraints require terminating the mission
(up to ~60 days). STO-2 will benefit tremendously from the heritage
and experience gained during the STO-1 campaign.

---------------------------------------------------------
Title: Micro-Sigmoids as Progenitors of Polar Coronal Jets
Authors: Raouafi, N. -E.; Bernasconi, P. N.; Rust, D. M.; Georgoulis,
M. K.
2010arXiv1009.2951R Altcode:
Observations from the Hinode X-ray telescope (XRT) are used to study
the structure of X-ray bright points (XBPs), sources of coronal
jets. Several jet events are found to erupt from S-shaped bright
points, suggesting that coronal micro-sigmoids are progenitors of the
jets. The observations may help to explain numerous characteristics
of coronal jets, such as helical structures and shapes. They also
suggest that solar activity may be self-similar within a wide range
of scales in terms of both properties and evolution of the observed
coronal structures.

---------------------------------------------------------
Title: Micro-sigmoids as Progenitors of Coronal Jets: Is Eruptive
Activity Self-similarly Multi-scaled?
Authors: Raouafi, N. -E.; Georgoulis, M. K.; Rust, D. M.; Bernasconi,
P. N.
2010ApJ...718..981R Altcode: 2010arXiv1005.4042R
Observations from the X-ray telescope (XRT) on Hinode are used to study
the nature of X-ray-bright points, sources of coronal jets. Several
jet events in the coronal holes are found to erupt from small-scale,
S-shaped bright regions. This finding suggests that coronal
micro-sigmoids may well be progenitors of coronal jets. Moreover,
the presence of these structures may explain numerous observed
characteristics of jets such as helical structures, apparent transverse
motions, and shapes. Analogous to large-scale sigmoids giving rise to
coronal mass ejections (CMEs), a promising future task would perhaps
be to investigate whether solar eruptive activity, from coronal jets to
CMEs, is self-similar in terms of properties and instability mechanisms.

---------------------------------------------------------
Title: The Stratospheric THz Observatory (STO)
Authors: Walker, C.; Kulesa, C.; Bernasconi, P.; Eaton, H.; Rolander,
N.; Groppi, C.; Kloosterman, J.; Cottam, T.; Lesser, D.; Martin,
C.; Stark, A.; Neufeld, D.; Lisse, C.; Hollenbach, D.; Kawamura,
J.; Goldsmith, P.; Langer, W.; Yorke, H.; Sterne, J.; Skalare, A.;
Mehdi, I.; Weinreb, S.; Kooi, J.; Stutzki, J.; Graf, U.; Brasse, M.;
Honingh, C.; Simon, R.; Akyilmaz, M.; Puetz, P.; Wolfire, Mark
2010SPIE.7733E..0NW Altcode: 2010SPIE.7733E..20W
The Stratospheric TeraHertz Observatory (STO) is a NASA funded,
Long Duration Balloon (LDB) experiment designed to address a key
problem in modern astrophysics: understanding the Life Cycle of the
Interstellar Medium (ISM). STO will survey a section of the Galactic
plane in the dominant interstellar cooling line [C II] (1.9 THz) and
the important star formation tracer [N II] (1.46 THz) at ~1 arc minute
angular resolution, sufficient to spatially resolve atomic, ionic and
molecular clouds at 10 kpc. STO itself has three main components; 1) an
80 cm optical telescope, 2) a THz instrument package, and 3) a gondola
[1]. Both the telescope and gondola have flown on previous experiments
[2,3]. They have been reoptimized for the current mission. The science
flight receiver package will contain four [CII] and four [NII] HEB
mixers, coupled to a digital spectrometer. The first engineering test
flight of STO was from Ft. Sumner, NM on October 15, 2009. The ~30
day science flight is scheduled for December 2011.

---------------------------------------------------------
Title: The "Sigmoid Sniffer” and the "Advanced Automated Solar
Filament Detection and Characterization Code” Modules
Authors: Raouafi, Noureddine; Bernasconi, P. N.; Georgoulis, M. K.
2010AAS...21640232R Altcode:
We present two pattern recognition algorithms, the "Sigmoid
Sniffer” and the "Advanced Automated Solar Filament Detection and
Characterization Code,” that are among the Feature Finding modules
of the Solar Dynamic Observatory: 1) Coronal sigmoids visible
in X-rays and the EUV are the result of highly twisted magnetic
fields. They can occur anywhere on the solar disk and are closely
related to solar eruptive activity (e.g., flares, CMEs). Their
appearance is typically synonym of imminent solar eruptions, so
they can serve as a tool to forecast solar activity. Automatic
X-ray sigmoid identification offers an unbiased way of detecting
short-to-mid term CME precursors. The "Sigmoid Sniffer” module is
capable of automatically detecting sigmoids in full-disk X-ray images
and determining their chirality, as well as other characteristics. It
uses multiple thresholds to identify persistent bright structures on
a full-disk X-ray image of the Sun. We plan to apply the code to X-ray
images from Hinode/XRT, as well as on SDO/AIA images. When implemented
in a near real-time environment, the Sigmoid Sniffer could allow 3-7
day forecasts of CMEs and their potential to cause major geomagnetic
storms. 2)The "Advanced Automated Solar Filament Detection and
Characterization Code” aims to identify, classify, and track solar
filaments in full-disk Hα images. The code can reliably identify
filaments; determine their chirality and other relevant parameters
like filament area, length, and average orientation with respect to
the equator. It is also capable of tracking the day-by-day evolution
of filaments as they traverse the visible disk. The code was tested by
analyzing daily Hα images taken at the Big Bear Solar Observatory from
mid-2000 to early-2005. It identified and established the chirality
of thousands of filaments without human intervention.

---------------------------------------------------------
Title: Computer Vision for SDO: First Results from the SDO Feature
Finding Algorithms
Authors: Martens, Petrus C.; Attrill, G.; Davey, A.; Engell, A.;
Farid, S.; Grigis, P.; Kasper, J.; Korreck, K.; Saar, S.; Su, Y.;
Testa, P.; Wills-Davey, M.; Bernasconi, P.; Raouafi, N.; Georgoulis,
M.; Deforest, C.; Peterson, J.; Berghoff, T.; Delouille, V.; Hochedez,
J.; Mampaey, B.; Verbeek, C.; Cirtain, J.; Green, S.; Timmons, R.;
Savcheva, A.; Angryk, R.; Wiegelmann, T.; McAteer, R.
2010AAS...21630804M Altcode:
The SDO Feature Finding Team produces robust and very efficient
software modules that can keep up with the relentless SDO data stream,
and detect, trace, and analyze a large number of phenomena including:
flares, sigmoids, filaments, coronal dimmings, polarity inversion
lines, sunspots, X-ray bright points, active regions, coronal holes,
EIT waves, CME's, coronal oscillations, and jets. In addition we track
the emergence and evolution of magnetic elements down to the smallest
features that are detectable, and we will also provide at least four
full disk nonlinear force-free magnetic field extrapolations per day. During SDO commissioning we will install in the near-real time data
pipeline the modules that provide alerts for flares, coronal dimmings,
and emerging flux, as well as those that trace filaments, sigmoids,
polarity inversion lines, and active regions. We will demonstrate
the performance of these modules and illustrate their use for science
investigations.

---------------------------------------------------------
Title: The Stratospheric THz Observatory (STO): 1st Test Flight
Authors: Walker, C.; Kulesa, C.; Koostermann, J.; Cottam, T.; Groppi,
C.; Bernasconi, P.; Eaton, H.; Rolander, N.; Neufeld, D.; Lisse, C.;
Stark, A.; Hollenbach, D.; Kawamura, J.; Goldsmith, P.; Langer, W.;
Yorke, H.; Sterne, J.; Skalare, A.; Mehdi, I.; Weinreb, S.; Kooi, J.;
Stutzski, J.; Graf, U.; Honingh, C.; Puetz, P.; Martin, C.; Lesser,
D.; Wolfire, Mark
2010stt..conf...46W Altcode:
No abstract at ADS

---------------------------------------------------------
Title: Automated Feature and Event Detection with SDO AIA and HMI Data
Authors: Davey, Alisdair; Martens, P. C. H.; Attrill, G. D. R.;
Engell, A.; Farid, S.; Grigis, P. C.; Kasper, J.; Korreck, K.; Saar,
S. H.; Su, Y.; Testa, P.; Wills-Davey, M.; Savcheva, A.; Bernasconi,
P. N.; Raouafi, N. -E.; Delouille, V. A.; Hochedez, J. F. .; Cirtain,
J. W.; Deforest, C. E.; Angryk, R. A.; de Moortel, I.; Wiegelmann,
T.; Georgouli, M. K.; McAteer, R. T. J.; Hurlburt, N.; Timmons, R.
2010cosp...38.2878D Altcode: 2010cosp.meet.2878D
The Solar Dynamics Observatory (SDO) represents a new frontier in
quantity and quality of solar data. At about 1.5 TB/day, the data will
not be easily digestible by solar physicists using the same methods
that have been employed for images from previous missions. In order for
solar scientists to use the SDO data effectively they need meta-data
that will allow them to identify and retrieve data sets that address
their particular science questions. We are building a comprehensive
computer vision pipeline for SDO, abstracting complete metadata
on many of the features and events detectable on the Sun without
human intervention. Our project unites more than a dozen individual,
existing codes into a systematic tool that can be used by the entire
solar community. The feature finding codes will run as part of the SDO
Event Detection System (EDS) at the Joint Science Operations Center
(JSOC; joint between Stanford and LMSAL). The metadata produced will
be stored in the Heliophysics Event Knowledgebase (HEK), which will be
accessible on-line for the rest of the world directly or via the Virtual
Solar Observatory (VSO) . Solar scientists will be able to use the
HEK to select event and feature data to download for science studies.

---------------------------------------------------------
Title: Solar Magnetic Helicity Injected into the Heliosphere:
Magnitude, Balance, and Periodicities Over Solar Cycle 23
Authors: Georgoulis, M. K.; Rust, D. M.; Pevtsov, A. A.; Bernasconi,
P. N.; Kuzanyan, K. M.
2009ApJ...705L..48G Altcode:
Relying purely on solar photospheric magnetic field measurements that
cover most of solar cycle 23 (1996-2005), we calculate the total
relative magnetic helicity injected into the solar atmosphere, and
eventually shed into the heliosphere, over the latest cycle. Large
active regions dominate the helicity injection process with ~5.7
× 1045 Mx2 of total injected helicity. The
net helicity injected is lsim1% of the above output. Peculiar
active-region plasma flows account for ~80% of this helicity; the
remaining ~20% is due to solar differential rotation. The typical
helicity per active-region CME ranges between (1.8-7) × 1042
Mx2 depending on the CME velocity. Accounting for various
minor underestimation factors, we estimate a maximum helicity injection
of ~6.6 × 1045 Mx2 for solar cycle 23. Although
no significant net helicity exists over both solar hemispheres,
we recover the well-known hemispheric helicity preference, which is
significantly enhanced by the solar differential rotation. We also
find that helicity injection in the solar atmosphere is an inherently
disorganized, impulsive, and aperiodic process.

---------------------------------------------------------
Title: Computer Vision for The Solar Dynamics Observatory
Authors: Martens, Petrus C.; Angryk, R. A.; Bernasconi, P. N.; Cirtain,
J. W.; Davey, A. R.; DeForest, C. E.; Delouille, V. A.; De Moortel,
I.; Georgoulis, M. K.; Grigis, P. C.; Hochedez, J. E.; Kasper, J.;
Korreck, K. E.; Reeves, K. K.; Saar, S. H.; Savcheva, A.; Su, Y.;
Testa, P.; Wiegelmann, T.; Wills-Davey, M.
2009SPD....40.1711M Altcode:
NASA funded a large international consortium last year to produce
a comprehensive system for automated feature recognition in SDO
images. The data we consider are all AIA and EVE data plus surface
magnetic field images from HMI. Helioseismology is addressed by another
group. We will produce robust and very efficient software modules
that can keep up with the relentless SDO data stream and detect, trace,
and analyze a large number of phenomena, including: flares, sigmoids,
filaments, coronal dimmings, polarity inversion lines, sunspots,
X-ray bright points, active regions, coronal holes, EIT waves, CME's,
coronal oscillations, and jets. In addition we will track the emergence
and evolution of magnetic elements down to the smallest features
that are detectable, and we will also provide at least four full
disk nonlinear force-free magnetic field extrapolations per day. A completely new software element that rounds out this suite is a
trainable feature detection module, which employs a generalized image
classification algorithm to produce the texture features of the images
analyzed. A user can introduce a number of examples of the phenomenon
looked and the software will return images with similar features. We
have tested a proto-type on TRACE data, and were able to "train" the
algorithm to detect sunspots, active regions, and loops. Such a module
can be used to find features that have not even been discovered yet,
as, for example, sigmoids were in the pre-Yohkoh era. Our codes
will produce entries in the Helio Events Knowledge base, and that will
permit users to locate data on individual events as well as carry out
statistical studies on large numbers of events, using the interface
provided by the Virtual Solar Observatory.

---------------------------------------------------------
Title: Just how much Helicity did the Sun Shed in Solar Cycle
23? Magnitude, Balance, Periodicities, and Further Implications
Authors: Georgoulis, Manolis K.; Rust, D. M.; Pevtsov, A. A.;
Bernasconi, P. N.; Kuzanyan, K. M.
2009SPD....40.0606G Altcode:
Using solar magnetic field measurements, we calculate the total
relative magnetic helicity injected in the solar atmosphere and
eventually transported to the heliosphere in the course of the
latest solar cycle. We report on (i) the magnitude of the heliospheric
helicity over cycle 23, (ii) the net helicity and its significance,
and (iii) the possible periodicities of helicity injection in
the solar atmosphere. Our simple calculations raise several questions
regarding the fundamental nature of solar magnetism. The lack of
significant net helicity may place the solar dynamo in the category
of astrophysical dynamos without a net helicity effect over an
average time scale. The strong enhancement of the hemispheric helicity
preference by solar differential rotation - although the latter has a
much weaker effect than intrinsic active-region plasma flows - warrants
further investigation. Finally, the absence of any credible periodicity
of helicity injection, in spite of numerous reported periodicities in
solar activity, perhaps prompts the re-evaluation of the notion that the
Sun works through a sequence of internal cycles: active-region emergence
and evolution appears as an inherently disorganized, aperiodic process.

---------------------------------------------------------
Title: Recent Anomalous TSI Decrease Not Due To Low Polar Facula and
Network Areas: Time to Broaden Our View of Solar Luminosity Variation?
Authors: Foukal, Peter V.; Bernasconi, P.; Frohlich, C.
2009SPD....40.1113F Altcode:
Total solar irradiance (TSI) values measured during the present activity
minimum by the VIRGO, ACRIM, and TIM radiometers are significantly (
0.018% +/- 0.006 % rms) lower than reported during the last minimum
in 1996 (1). This decrease represents 1/4 the amplitude of 11 -
yr TSI variation. Differences in spots, faculae and active network
cannot account for this anomalous decrease. A sufficient difference
in the TSI contribution from quiet network also seems unlikely, since
the solar microwave flux index, F10.7, has dipped only 4 % below
its 1996 minimum. This is an order of magnitude less than required
to explain the TSI decrease by a decline in network area. The
remaining explanation in terms of photospheric magnetic structures,
might lie in a decrease in the area of polar faculae, whose cycle
amplitude is presently at a minimum for this century. We evaluate
their TSI contribution using area and contrast measurements with
the Solar Bolometric Imager (SBI), together with polar facula counts
(2). We find that their TSI contribution between the present and 1996
activity minima, is below 0.002%. This is again, an order of magnitude
below the observed TSI decrease. We conclude that the anomalous TSI
decrease is unlikely to be caused by photospheric magnetic changes. This
suggests that solar luminosity may be able to change significantly
over decadal time scales through an as- yet- unidentified, relatively
shallow mechanism that avoids the 10*5 year thermal relaxation time of
the solar convection zone. This work was supported at Heliophysics,
Inc by NSF grant ATM 0718305, and at APL by NASA grant NNG 05WC07G References: 1. Frohlich, C. 2008, AGU Fall Meeting, Abstract #
SH21C-05. 2. Sheeley, N. 2008, Ap.J. , 680, 1553.

---------------------------------------------------------
Title: A Test Flight Instrument for the Stratospheric Terahertz
Observatory (STO)
Authors: Walker, C.; Kulesa, C.; Groppi, C.; Young, E.; Bernasconi,
P.; Eaton, H.; Rolander, N.; Lisse, C.; Hollenbach, D.; Kawamura,
J.; Goldsmith, P.; Langer, W.; Yorke, H.; Sterne, J.; Skalare, A.;
Mehdi, I.; Weinreb, S.; Kooi, J.; Stutzki, J.; Graf, U.; Honingh,
C.; Pütz, P.; Martin, C. L.
2009stt..conf..107W Altcode:
No abstract at ADS

---------------------------------------------------------
Title: Solar Network Bolometric Properties at Minimum of Activity
Observed by the Solar Bolometric Imager
Authors: Bernasconi, P. N.; Foukal, P. V.
2008AGUFMSH23A1625B Altcode:
On September 13 2007, the Solar Bolometric Imager (SBI) observed the Sun
in wide band spectrally integrated for 16 hours while suspended from
a balloon at ~120,000 feet altitude above New Mexico. SBI represents
a totally new approach in finding the sources of the solar irradiance
variation. Its detector is an array of 320x240 thermal IR elements
whose spectral sensitivity has been extended and flattened by a layer
of gold-black deposited on its IR sensitive surface. The combination
of bolometric array and telescope, a 30- cm Dall-Kirkham with uncoated
primary and secondary Pyrex mirrors, provide an image of the Sun with
constant spectral response between ~ 280 and 2600 nm, over a field of
view of 960 x 720 arcsec with a pixel size of 3 arcsec. The September
13, 2007 flight provided bolometric (integrated light) maps of the
photosphere when the Sun was near a minimum of activity. At the time of
the flight no active regions were present giving us the opportunity to
measure with high accuracy the bolometric contrast of the weak solar
magnetic network from Sun center to the limb. The network was easily
detectable by SBI near the limb. We measured an average bolometric
contrast of ~ 0.8 to 1.0 %, which is slightly above the 5-minute
oscillation brightness signal (the most prominent solar induced noise
source for us). We were also able to detect the bolometric brightness
signature of network near Sun center by averaging 720 bolometric images
taken close to Sun center over a period of 1 hour. The resulting RMS
noise was &lt; 0.02% and most of the 5-minute oscillation brightness was
removed in the average. This enabled us to measure an average network
bolometric contrast at Sun center of 0.25% with a spread of about ±
0.05%. Ours is the first bolometric measurement (constant spectral
sensitivity from 280 to 2600 nm) of the center-to-limb contrast of
magnetic network. Our observations demonstrate that SBI can accurately
measure the bolometric contrast of even quiet network across the solar
disk. These measurements will enable a more precise estimate of the
TSI contribution from changes of the enhanced magnetic network, which
consist of larger elements than the quiet network. This will enable
us to determine whether other low level brightness sources besides
faculae and spots contribute to TSI and evaluate their possible long
term influence in TSI change and climate.

---------------------------------------------------------
Title: Barium strontium titanate (BST) pyroelectric detector for
bolometric solar imaging
Authors: Noble, M.; Bernasconi, P.; Francomacaro, A.; Eaton, H.;
Carkhuff, B.; Foukal, P.
2008SPIE.7055E..0AN Altcode: 2008SPIE.7055E...6N
The Solar Bolometric Imager (SBI) is an imaging solar telescope
assembly that employs a novel single-detector broadband bolometric
measurement technique. An uncooled thermal IR imaging detector is
coated with a thin gold-black film that absorbs over 98% of the solar
spectrum. The absorbed energy is then re-radiated in the thermal IR
and sampled by the detector array. This technique [4] provides an
evenly weighted integrated responsivity that spans the majority of the
solar spectrum (0.2-2.5μm). We present here performance results from
the follow-on gold-black deposition process investigation, radiation
testing results, spacecraft instrument design and some of the prototype
detector/imaging system's flight performance and calibration data from
our 2007 Ft. Sumner balloon flight that demonstrates the instrument
met or exceeded all of its specification.

---------------------------------------------------------
Title: Do Photospheric Brightness Structures Outside Magnetic Flux
Tubes Contribute to Solar Luminosity Variation?
Authors: Bernasconi, P. N.; Foukal, P. V.
2008AGUSMSP53B..07B Altcode:
Variations in total solar irradiance (TSI) correlate well with changes
in projected area of photospheric magnetic flux tubes associated with
dark sunspots and bright faculae in active regions and network. This
correlation does not, however, rule out possible TSI contributions from
photospheric brightness inhomogeneities located outside flux tubes,
and spatially correlated with them. Previous reconstructions of TSI
report agreement with radiometry that seems to rule out significant
"extra-flux tube" contributions. We show that these reconstructions are
more sensitive to the facular contrasts used than has been generally
recognized. Measurements with the Solar Bolometric Imager (SBI)
provide the first reliable support for the relatively high, wide-band,
disc-center contrasts required to produce 10% rms agreement. Longer-term
bolometric imaging will be required to determine whether the small
but systematic TSI residuals we see here are caused by remaining
errors in spot and facular areas and contrasts, or by extra-flux
tube brightness structures such as bright rings around sunspots, or
"convective stirring" around active regions.

---------------------------------------------------------
Title: Preliminary Results Of the 2007 Flight of the Solar Bolometric
Imager at Solar Minimum
Authors: Bernasconi, P. N.; Foukal, P. V.; Eaton, H. H.; Noble, M.
2008AGUSMSP41B..05B Altcode:
On September 13 2007, the Solar Bolometric Imager (SBI) successfully
observed the Sun for several hours while suspended from a balloon in
the stratosphere above New Mexico. The SBI represents a totally new
approach in finding the sources of the solar irradiance variation. The
SBI detector is an array of 320x240 thermal IR elements whose spectral
absorptance has been extended and flattened by a deposited layer of
gold-black. The telescope is a 30-cm Dall-Kirkham with uncoated primary
and secondary Pyrex mirrors. The combination of telescope and bolometric
array provide an image of the Sun with a constant spectral response
between ~ 280 and 2600 nm, over a field of view of 960 x 720 arcsec
with a pixel size of 3 arcsec. This is the second successful flight
of SBI, following a successful one on September 2003 which produced
the first measurements in broad band of the center-to-limb variation
of bolometric facular contrast (a flight attempt from Antarctica in
2006 was aborted). This latest flight provided bolometric (integrated
light) maps of the solar photosphere during a time of minimum of solar
activity. The SBI imagery will enable us to evaluate the photometric
contribution of weak magnetic structures (e.g. network) more accurately
than has been achievable with spectrally selective imaging over
restricted wavebands. It will also enable us to investigate the
presence, if any, of other thermal structures unrelated to magnetic
activity, such as e.g. giant cells and pole-to-equator temperature
gradients. During the 16 hour flight the SBI gathered several thousand
bolometric images that are now being processed to produce full-disk
maps of spatial variation in total solar output at solar minimum. The
SBI flight is also providing important engineering data to validate the
space worthiness of the novel gold-blackened thermal array detectors. In
this paper we will briefly describe the characteristics of the SBI,
its in-flight performance, and we will present the first results of
the analysis of the bolometric images.

---------------------------------------------------------
Title: The Stratospheric TeraHertz Observatory (STO)
Authors: Walker, C. K.; Kulesa, C. A.; Groppi, C. E.; Young, E.;
McMahon, T.; Bernasconi, P.; Lisse, C.; Neufeld, D.; Hollenbach,
D.; Kawamura, J.; Goldsmith, P.; Langer, W.; Yorke, H.; Sterne, J.;
Skalare, A.; Mehdi, I.; Weinreb, S.; Kooi, J.; Stutzki, J.; Graf,
U.; Honingh, C.; Puetz, P.; Martin, C.; Wolfire, M.
2008stt..conf...28W Altcode:
No abstract at ADS

---------------------------------------------------------
Title: Do Photospheric Brightness Structures Outside Magnetic Flux
Tubes Contribute to Solar Luminosity Variation?
Authors: Foukal, Peter; Bernasconi, Pietro N.
2008SoPh..248....1F Altcode: 2008SoPh..tmp...33F
Variations in total solar irradiance (TSI) correlate well with changes
in projected area of photospheric magnetic flux tubes associated with
dark sunspots and bright faculae in active regions and network. This
correlation does not, however, rule out possible TSI contributions from
photospheric brightness inhomogeneities located outside flux tubes
and spatially correlated with them. Previous reconstructions of TSI
report agreement with radiometry that seems to rule out significant
"extra-flux-tube" contributions. We show that these reconstructions are
more sensitive to the facular contrasts used than has been generally
recognized. Measurements with the Solar Bolometric Imager (SBI)
provide the first reliable support for the relatively high, wide-band,
disk-center contrasts required to produce 10% rms agreement. Longer term
bolometric imaging will be required to determine whether the small but
systematic TSI residuals we see here are caused by remaining errors in
spot and facular areas and contrasts or by extra-flux-tube brightness
structures such as bright rings around sunspots or "convective stirring"
around active regions.

---------------------------------------------------------
Title: Do Photospheric Brightness Structures Outside Magnetic Flux
Tubes Contribute to Solar Luminosity Variation?
Authors: Bernasconi, P. N.; Foukal, P.
2007AGUFMGC31B0345B Altcode:
Variations in total solar irradiance (TSI) correlate well with changes
in projected area of photospheric magnetic flux tubes associated with
spots, faculae and network. This correlation does not, however, rule out
possible TSI contributions from photospheric brightness inhomogeneities
located outside flux tubes, and spatially correlated with them. Previous
reconstructions report 10% amplitude agreement with radiometry that
seems to rule out significant extra-flux tube contributions. We show
that, while these reconstructions are insensitive to behavior of near-
limb facular contrast, their sensitivity to contrasts on the disc is
relatively high. Given this sensitivity, previously used observational
and theoretical approximations to wide-band facular contrast are too
uncertain to support claims of 10% reconstruction accuracy. Recent
measurements with the Solar Bolometric Imager (SBI) provide the first
observational support for the relatively high wide-band, disc-center
contrasts required to produce 10% rms agreement. Longer-term bolometric
imaging to measure areas and bolometric contrasts homogeneously
will be required to determine whether the systematic TSI residuals
we see are caused mainly by uncertainties in sunspot contrasts, or
by extra-flux tube brightness structures due to bright spot rings or
convective stirring.

---------------------------------------------------------
Title: Emergence of undulatory magnetic flux tubes by small scale
reconnections
Authors: Pariat, E.; Aulanier, G.; Schmieder, B.; Georgoulis, M. K.;
Rust, D. M.; Bernasconi, P. N.
2006AdSpR..38..902P Altcode:
With Flare Genesis Experiment (FGE), a balloon borne observatory
launched in Antarctica on January 2000, series of high spatial
resolution vector magnetograms, Dopplergrams, and Hα filtergrams
have been obtained in an emerging active region (AR 8844). Previous
analyses of this data revealed the occurence of many short-lived
and small-scale H α brightenings called 'Ellerman bombs'
(EBs) within the AR. We performed an extrapolation of the field above
the photosphere using the linear force-free field approximation. The
analysis of the magnetic topology reveals a close connexion between
the loci of EBs and the existence of "Bald patches" (BP) regions
(BPs are regions where the vector magnetic field is tangential to
the photosphere). Some of these EBs/BPs are magnetically connected
by low-lying field lines, presenting a serpentine shape. This results
leads us to conjecture that arch filament systems and active regions
coronal loops do not result from the smooth emergence of large scale
Ω-loops, but rather from the rise of flat undulatory flux tubes which
get released from their photospheric anchorage by reconnection at BPs,
which observational signature is Ellerman bombs.

---------------------------------------------------------
Title: Observation of Small Scale Reconnection Role in Undulated
Flux Tube Emergence
Authors: Pariat, E.; Aulanier, G.; Schmieder, B.; Georgoulis, M. K.;
Rust, D. M.; Bernasconi, P. N.
2005ESASP.596E..34P Altcode: 2005ccmf.confE..34P
No abstract at ADS

---------------------------------------------------------
Title: Can Changing Sunspot and Facular Areas Reproduce the Amplitude
of Total Irradiance Variations?(Look,Mom; No Free Parameters!)
Authors: Foukal, P.; Bernasconi, P. N.; Walton, S. R.
2005AGUSMSH22B..02F Altcode:
Empirical models of total solar irradiance variation demonstrate a
high correlation between observed irradiance fluctuations and the
changing areas of spots and faculae. However, the contrast of these
structures (especially the faculae) in integrated light is still
uncertain. Consequently, the agreement in amplitude of the measured
and modeled irradiance time series remains poorly known. Recently, the
first measurements of facular contrast in broad - band integrated light
were obtained using the balloon -borne Solar Bolometric Imager (Foukal
et al., Ap.J. Letts 611,57,2004). These measurements, obtained over
approximately the same wavelength range accepted by radiometers such as
VIRGO or ACRIM, enable the first reconstruction of the total irradiance
expected from spots and faculae, with no free parameters. We compare
this reconstruction with the radiometric record to determine whether
other contributions besides the darkness of spots and brightness of
faculae are required to explain solar irradiance variation, at least
over rotational time scales.

---------------------------------------------------------
Title: Advanced Automated Solar Filament Detection And
Characterization Code: Description, Performance, And Results
Authors: Bernasconi, Pietro N.; Rust, David M.; Hakim, Daniel
2005SoPh..228...97B Altcode:
We present a code for automated detection, classification, and tracking
of solar filaments in full-disk Hα images that can contribute
to Living With a Star science investigations and space weather
forecasting. The program can reliably identify filaments; determine
their chirality and other relevant parameters like filament area,
length, and average orientation with respect to the equator. It is
also capable of tracking the day-by-day evolution of filaments while
they travel across the visible disk. The code was tested by analyzing
daily Hα images taken at the Big Bear Solar Observatory from mid-2000
until beginning of 2005. It identified and established the chirality
of thousands of filaments without human intervention. We compared
the results with a list of filament proprieties manually compiled by
Pevtsov, Balasubramaniam and Rogers (2003) over the same period of
time. The computer list matches Pevtsov's list with a 72% accuracy. The
code results confirm the hemispheric chirality rule stating that dextral
filaments predominate in the north and sinistral ones predominate in the
south. The main difference between the two lists is that the code finds
significantly more filaments without an identifiable chirality. This may
be due to a tendency of human operators to be biased, thereby assigning
a chirality in less clear cases, while the code is totally unbiased. We
also have found evidence that filaments obeying the chirality rule
tend to be larger and last longer than the ones that do not follow the
hemispherical rule. Filaments adhering to the hemispheric rule also tend
to be more tilted toward the equator between latitudes 10∘
and 30∘, than the ones that do not.

---------------------------------------------------------
Title: Finding the sources of irradiance variation at sunspot
minimum .
Authors: Bernasconi, P. N.; Foukal, P.; Rust, D. M.; LaBonte, B. J.
2005MmSAI..76..907B Altcode:
In 2006-2007 the Solar Bolometric Imager (SBI) will operate in the polar
stratosphere where near-space conditions can be attained for 10 to 30
days. The instrument will provide bolometric (wavelength-integrated
light) and color temperature images of the Sun. At the upcoming sunspot
minimum, SBI observations will be able to detect subtle sources
of solar irradiance variation with the least confusion by signals
from the magnetic fields. This is the best observational approach
to characterizing potential causes of the long-term irradiance
variations. Possible predicted sources of secular variability
include torsional waves and meridional flow variations. SBI uses a
30-cm diameter F/12 Dall-Kirkham telescope with uncoated mirrors, and
neutral density filters to provide broadband (bolometric) sensitivity
that varies only by ±7% over the wavelengths from 0.31 mu m to 2.6
mu m. Inferred solar irradiance variations will be compared with space
based full-disk radiometric measurements.

---------------------------------------------------------
Title: Finding the Sources of Irradiance Variation at Sunspot Minimum
Authors: Rust, D. M.; Bernasconi, P. N.; Foukal, P. V.; Labonte, B. J.
2004AGUFMSH51E..02R Altcode:
In 2006-2007 the Solar Bolometric Imager (SBI) and the Multi-Spectral
Imager (MSI) will operate in the polar stratosphere where near-space
conditions can be attained for 10 to 20 days. The instruments will
provide bolometric (wavelength-integrated light) and color temperature
images of the Sun. At the upcoming sunspot minimum, SBI observations
will be able to detect subtle sources of solar irradiance variation
with the least confusion by signals from the magnetic fields. This is
the best observational approach to characterizing potential causes
of the long-term irradiance variations. Possible predicted sources
of secular variability include torsional waves and meridional flow
variations. SBI uses a 30-cm diameter F/12 Dall-Kirkham telescope with
uncoated mirrors, and neutral density filters to provide broadband
(bolometric) sensitivity that varies only by ±7 percent over the
wavelengths from 0.28 microns to 2.6 microns. The MSI is a CCD-based
imager that will provide diagnostics of solar magnetic and thermal
structures while SBI assesses their radiance. Sunspots, faculae
and magnetic network will be identified from the MSI images. Sonic
filtering of the MSI images will isolate the oscillatory signal. That
signal will be used to remove oscillations from SBI averages to reduce
the solar noise. Inferred solar irradiance variations will be compared
with SORCE/TIM and ACRIMSAT measurements. The images and data products
will be openly available via the Web.

---------------------------------------------------------
Title: An Integrated Program to Forecast Geostorms
Authors: Labonte, B. J.; Rust, D.; Bernasconi, P.; Georgoulis, M.
2004AGUFMSA51B0243L Altcode:
We have developed several operational products and automated tools for
assessing the helicity content of solar regions and their probability of
launching a geoeffective coronal mass ejection. These include detection
of active region sigmoids, measurement of magnetic helicity injection
in active regions, measurement of the sense of helicity in solar
filaments, and the estimate of magnetic helicity content of active
regions from vector magnetogram observations. In this presentation
we discuss a new program to integrate the separate products and tools
into a single product that provides a quantitative mid-term forecast
of solar activity that results in geomagnetic storms.

---------------------------------------------------------
Title: Advanced Automated Solar Filament Detection and
Characterization Code: Description, Performance, and Results
Authors: Bernasconi, P. N.; Rust, D. M.
2004AGUFMSA51B0235B Altcode:
We have developed a code for automated detection and classification
of solar filaments in full-disk H-alpha images that can contribute
to Living With a Star science investigations and space weather
forecasting. The program can reliably identify filaments, determine
their chirality and other relevant parameters like the filaments
area and their average orientation with respect to the equator, and
is capable of tracking the day-by-day evolution of filaments while
they travel across the visible disk. Detecting the filaments when they
appear and tracking their evolution can provide not only early warnings
of potentially hazardous conditions but also improve our understanding
of solar filaments and their implications for space weather at 1 AU. The
code was recently tested by analyzing daily H-alpha images taken at the
Big Bear Solar Observatory during a period of four years (from mid 2000
until mid 2004). It identified and established the chirality of more
than 5000 filaments without human intervention. We compared the results
with the filament list manually compiled by Pevtsov et al. (2003)
over the same period of time. The computer list matches the Pevtsov
et al. list fairly well. The code results confirm the hemispherical
chirality rule: dextral filaments predominate in the north and sinistral
ones predominate in the south. The main difference between the two
lists is that the code finds significantly more filaments without
an identifiable chirality. This may be due to a tendency of human
operators to be biased, thereby assigning a chirality in less clear
cases, while the code is totally unbiased. We also have found evidence
that filaments with definite chirality tend to be larger and last longer
than the ones without a clear chirality signature. We will describe the
major code characteristics and present and discuss the tests results.

---------------------------------------------------------
Title: Resistive Emergence of Undulatory Flux Tubes
Authors: Pariat, E.; Aulanier, G.; Schmieder, B.; Georgoulis, M. K.;
Rust, D. M.; Bernasconi, P. N.
2004ApJ...614.1099P Altcode:
During its 2000 January flight, the Flare Genesis Experiment observed
the gradual emergence of a bipolar active region, by recording a series
of high-resolution photospheric vector magnetograms and images in the
blue wing of the Hα line. Previous analyses of these data revealed the
occurrence of many small-scale, transient Hα brightenings identified
as Ellerman bombs (EBs). They occur during the flux emergence,
and many of them are located near moving magnetic dipoles in which
the vector magnetic field is nearly tangential to the photosphere. A
linear force-free field extrapolation of one of the magnetograms was
performed to study the magnetic topology of small-scale EBs and their
possible role in the flux emergence process. We found that 23 out of 47
EBs are cospatial with bald patches (BPs), while 15 are located at the
footpoints of very flat separatrix field lines passing through distant
BPs. We conclude that EBs can be due to magnetic reconnection, not only
at BP locations, but also along their separatrices, occurring in the
low chromosphere. The topological analysis reveals, for the first time,
that many EBs and BPs are linked by a hierarchy of elongated flux tubes
showing aperiodic spatial undulations, whose wavelengths are typically
above the threshold of the Parker instability. These findings suggest
that arch filament systems and coronal loops do not result from the
smooth emergence of large-scale Ω-loops from below the photosphere,
but rather from the rise of undulatory flux tubes whose upper parts
emerge because of the Parker instability and whose dipped lower parts
emerge because of magnetic reconnection. EBs are then the signature
of this resistive emergence of undulatory flux tubes.

---------------------------------------------------------
Title: Broadband Measurements of Facular Photometric Contrast Using
the Solar Bolometric Imager
Authors: Foukal, Peter; Bernasconi, Pietro; Eaton, Harry; Rust, David
2004ApJ...611L..57F Altcode:
We present the first photometric measurements of solar faculae in
broadband light. Our measurements were made during the recent flight of
the Solar Bolometric Imager (SBI), a 30 cm balloon-borne telescope that
imaged the Sun with a spectrally constant response between about 0.31
and 2.6 μm. Our curve of facular contrast versus limb distance agrees
well with values obtained by the blackbody correction of monochromatic
measurements. This decreases uncertainty in the facular irradiance
contribution, which limits searches for other possible mechanisms of
solar luminosity variation, besides changes of photospheric magnetism.

---------------------------------------------------------
Title: Solar constraints on new couplings between electromagnetism
and gravity
Authors: Solanki, S. K.; Preuss, O.; Haugan, M. P.; Gandorfer, A.;
Povel, H. P.; Steiner, P.; Stucki, K.; Bernasconi, P. N.; Soltau, D.
2004PhRvD..69f2001S Altcode: 2004gr.qc.....2055S
The unification of quantum field theory and general relativity is a
fundamental goal of modern physics. In many cases, theoretical efforts
to achieve this goal introduce auxiliary gravitational fields, ones
in addition to the familiar symmetric second-rank tensor potential
of general relativity, and lead to nonmetric theories because of
direct couplings between these auxiliary fields and matter. Here,
we consider an example of a metric-affine gauge theory of gravity in
which torsion couples nonminimally to the electromagnetic field. This
coupling causes a phase difference to accumulate between different
polarization states of light as they propagate through the metric-affine
gravitational field. Solar spectropolarimetric observations are reported
and used to set strong constraints on the relevant coupling constant k:
k2&lt;(2.5 km)2.

---------------------------------------------------------
Title: Emerging Flux and the Heating of Coronal Loops
Authors: Schmieder, B.; Rust, D. M.; Georgoulis, M. K.; Démoulin,
P.; Bernasconi, P. N.
2004ApJ...601..530S Altcode:
We use data collected by a multiwavelength campaign of observations
to describe how the fragmented, asymmetric emergence of magnetic flux
in NOAA active region 8844 triggers the dynamics in the active-region
atmosphere. Observations of various instruments on board Yohkoh, SOHO,
and TRACE complement high-resolution observations of the balloon-borne
Flare Genesis Experiment obtained on 2000 January 25. We find that
coronal loops appeared and evolved rapidly ~6+/-2 hr after the first
detection of emerging magnetic flux. In the low chromosphere, flux
emergence resulted in intense Ellerman bomb activity. Besides the
chromosphere, we find that Ellerman bombs may also heat the transition
region, which showed “moss” ~100% brighter in areas with Ellerman
bombs as compared to areas without Ellerman bombs. In the corona,
we find a spatiotemporal anticorrelation between the soft X-ray (SXT)
and the extreme ultraviolet (TRACE) loops. First, SXT loops preceded
the appearance of the TRACE loops by 30-40 minutes. Second, the TRACE
and SXT loops had different shapes and different footpoints. Third,
the SXT loops were longer and higher than the TRACE loops. We conclude
that the TRACE and the SXT loops were formed independently. TRACE loops
were mainly heated at their footpoints, while SXT loops brightened in
response to coronal magnetic reconnection. In summary, we observed a
variety of coupled activity, from the photosphere to the active-region
corona. Links between different aspects of this activity lead to
a unified picture of the evolution and the energy release in the
active region.

---------------------------------------------------------
Title: Emerging Flux and the Heating of Coronal Loops
Authors: Schmieder, B.; Démoulin, P.; Rust, D. M.; Georgoulis, M. K.;
Bernasconi, P. N.
2004IAUS..219..483S Altcode: 2003IAUS..219E..18S
We suggest that coronal loop heating is caused by dissipation of
magnetic energy as new magnetic flux emerges from the photosphere. Based
on data from a multi wavelength campaign of observations during the
flight of the Flare Genesis Experiment we describe how emergence
of flux from the photosphere appears directly to heat the corona
to 2-3 MK. Following intense heating the loops cool and become
visible through the filters of the TRACE (Transition Region and
Coronal Explorer)instrument at one million degrees. We determine the
relaxation time of the cooling and compare it withtheoretical heating
functions. The proposed mechanism is well accepted in flare loops but
we suggest that the mechanism is generally valid and helps to explain
the visibility of active region loops in transition region lines.

---------------------------------------------------------
Title: The solar bolometric imager
Authors: Bernasconi, P. N.; Eaton, H. A. C.; Foukal, P.; Rust, D. M.
2004AdSpR..33.1746B Altcode:
The balloon-borne Solar Bolometric Imager (SBI) will provide the first
bolometric (integrated light) maps of the solar photosphere. It will
evaluate the photometric contribution of magnetic structures more
accurately than has been possible with spectrally selective imaging
over restricted wavebands. More accurate removal of the magnetic
feature contribution will enable us to determine if solar irradiance
variation mechanisms exist other than the effects of photospheric
magnetism. The SBI detector is an array of 320 × 240 ferro-electric
thermal IR elements whose spectral absorptance has been extended and
flattened by a deposited layer of gold-black. The telescope itself is
a 30-cm Dall-Kirkham design with uncoated primary and secondary pyrex
mirrors. The combination of telescope and bolometric array provides
an image of the Sun with a flat spectral response between 0.28 and 2.6
μm, over a field of view of 917 × 687 arcsec, and a pixel size of 2.8
arcsec. After a successful set of ground-based tests, the instrument is
being readied for a one-day stratospheric balloon flight that will take
place in September 2003. The observing platform will be the gondola
previously used for the Flare Genesis Experiment (FGE), retrofitted
to house and control the SBI telescope and detector. The balloon
flight will enable SBI to image over essentially the full spectral
range accepted by non-imaging space-borne radiometers such as ACRIM,
making the data sets complementary. The SBI flight will also provide
important engineering data to validate the space worthiness of the
novel gold-blackened thermal array detectors, and verify the thermal
performance of the SBI's uncoated optics in a vacuum environment.

---------------------------------------------------------
Title: Emergence of undulatory magnetic flux tubes by small scale
reconnections
Authors: Pariat, E.; Aulanier, G.; Schmieder, B.; Georgoulis, M. K.;
Rust, D. M.; Bernasconi, P. N.
2004cosp...35.1482P Altcode: 2004cosp.meet.1482P
With Flare Genesis Experiment (FGE), a balloon borne observatory
launched in Antarctica on January 2000, series of high spatial
resolution vector magnetograms, Dopplergrams, and Hα filtergrams
have been obtained in an emerging active region (AR 8844). Previous
analyses of this data revealed the occurence of many short-lived and
small-scale Hα brightenings called 'Ellerman bombs' (EBs) within the
AR. We performed an extrapolation of the field above the photosphere
using the linear force-free field approximation. The analysis of the
magnetic topology reveals a close connexion between the loci of EBs
and the existence of “Bald patches” regions (BPs are regions where
the vector magnetic field is tangential to the photosphere). Among
47 identified EBs, we found that 23 are co-spatial with a BP, while
19 are located at the footpoint of very flat separatrix field lines
passing throught a distant BP. We reveal for the first time that
some of these EBs/BPs are magneticaly connected by low-lying lines,
presenting a 'sea-serpent' shape. This results leads us to conjecture
that arch filament systems and active regions coronal loops do not
result from the smooth emergence of large scale Ω loops, but rather
from the rise of flat undulatory flux tubes which get released from
their photospheric anchorage by reconnection at BPs, whose observational
signature is Ellerman bombs.

---------------------------------------------------------
Title: First Results Of The Solar Bolometric Imager
Authors: Bernasconi, P. N.; Foukal, P.; Eaton, H. H.; Rust, D. M.
2003AGUFMSH32A1101B Altcode:
On September 1 2003, the Solar Bolometric Imager (SBI) successfully
observed the Sun for several hours while suspended from a balloon in the
stratosphere above New Mexico. The SBI represents a totally new approach
in finding the sources of the solar irradiance variation. The mission
provided the first bolometric (integrated light) maps of the solar
photosphere, that will allow to evaluate the photometric contribution
of magnetic structures more accurately than has been achievable with
spectrally selective imaging over restricted wavebands. The more
accurate removal of the magnetic features contribution will enable
us to determine if solar irradiance variation mechanisms exist other
than the effects of photospheric magnetism. The SBI detector was an
array of 320 x 240 thermal IR elements whose spectral absorptance has
been extended and flattened by a deposited layer of gold-black. The
telescope was a 30-cm Dall-Kirkham with uncoated primary and secondary
pyrex mirrors. The combination of telescope and bolometric array
provided an image of the Sun with a flat spectral response between
0.28 and 2.6 microns, over a field of view of 917 x 687 arcsec with
a pixel size of 2.8 arcsec. The observing platform was the gondola
previously used for the Flare Genesis Experiment (FGE), retrofitted to
house and control the SBI telescope and detector. During the 9 hours
of flight the SBI gathered several thousand bolometric images that
are now being processed to produce the first maps of the total solar
irradiance. The SBI flight is also providing important engineering data
to validate the space worthiness of the novel gold-blackened thermal
array detectors, and to verify the thermal performance of the SBI's
uncoated optics in a vacuum environment. In this paper we will briefly
describe the characteristics of the SBI, its in flight performance,
and we will present the first results of the analysis of the bolometric
images. This work was funded by NASA under grant# NAG5-10998.

---------------------------------------------------------
Title: An Automated System for Detecting Sigmoids in Solar X-ray
Images
Authors: LaBonte, B. J.; Rust, D. M.; Bernasconi, P. N.
2003SPD....34.0504L Altcode: 2003BAAS...35R.814L
The probability of a coronal mass ejection (CME) occurring is linked
to the appearance of structures, called sigmoids, in satellite X-ray
images of the sun. By examination of near real time images, we can
detect sigmoids visually and estimate the probability of a CME and
the probability that it will cause a major geomagnetic storm. We
have devised a pattern recognition system to detect the sigmoids in
Yohkoh SXT and GOES SXI X-ray images automatically. When implemented
in a near real time environment, this system should allow long term,
3 - 7 day, forecasts of CMEs and their potential for causing major
geomagnetic storms.

---------------------------------------------------------
Title: The Solar Bolometric Imager: Characteristics and Performance.
Authors: Bernasconi, P. N.; Foukal, P.; Rust, D. M.
2003SPD....34.2002B Altcode: 2003BAAS...35..844B
The Solar Bolometric Imager (SBI) is an innovative solar telescope
capable of recording the first bolometric (integrated light) maps of the
photosphere. It will enable evaluation of the photometric contribution
of magnetic structures more accurately than has been achievable with
spectrally selective imaging. The SBI has an angular resolution of 5",
sufficient to distinguish sunspots, faculae and enhanced network. These
photospheric magnetic structures are known to be linked closely to
irradiance variations. Accurate removal of irradiance variations linked
to the magnetic features will enable us to determine if other solar
irradiance variation mechanisms exist. The SBI detector is an
array of 320 x 240 ferro-electric thermal IR elements whose spectral
absorptance has been extended and flattened by a deposited layer of
gold-black. The telescope is a 30-cm Dall-Kirkham design with uncoated
primary and secondary pyrex mirrors. The combination of telescope and
bolometric array provides an image of the sun with a flat spectral
response between 0.28 microns and 2.6 microns, over a field of view
of 917" x 687", and a pixel size of 2.8". After completion of ground
tests, the balloon-borne instrument will make a one-day stratospheric
flight in September 2003. Observing from an altitude of over 30
km, the SBI will image the sun over nearly the full spectral range
accepted by non-imaging satellite-borne radiometers such as ACRIM,
making the data sets complementary. The SBI flight will also provide
important engineering data to validate the space worthiness of the
novel gold-blackened thermal array detectors, and to verify the
thermal performance of the SBI's optics in a vacuum environment. Here we will describe the SBI in more detail and present the results
of various instrument performance tests, including solar observations
from the ground, in preparation for the balloon flight. This work
is funded by NASA under grant NAG5-10998.

---------------------------------------------------------
Title: Near-infrared chromospheric observatory
Authors: Labonte, Barry; Rust, David M.; Bernasconi, Pietro N.;
Georgoulis, Manolis K.; Fox, Nicola J.; Kalkofen, Wolfgang; Lin,
Haosheng
2003SPIE.4853..140L Altcode:
NICO, the Near Infrared Chromosphere Observatory, is a platform for
determining the magnetic structure and fources of heating for the
solar chromosphere. NICO, a balloon-borne observatory, will use the
largest solar telescope flying to map the magnetic fields, velocities,
and heating events of the chromosphere and photosphere in detail. NICO
will introduce new technologies to solar flight missions, such as
wavefront sensing for monitoring telescope alignment, real-time
correlation tracking and high-speed image motion compensation, and
wide aperture Fabry-Perot etalons for extended spectral scanning.

---------------------------------------------------------
Title: Flare Genesis Experiment: magnetic topology of Ellerman bombs
Authors: Schmieder, B.; Pariat, E.; Aulanier, G.; Georgoulis, M. K.;
Rust, D. M.; Bernasconi, P. N.
2002ESASP.506..911S Altcode: 2002svco.conf..911S; 2002ESPM...10..911S
Flare Genesis Experiment (FGE), a balloon borne Observatory was launched
in Antarctica on January 10, 2000 and flew during 17 days. FGE consists
of an 80 cm Cassegrain telescope with an F/1.5 ultra-low-expansion
glass primary mirror and a crystalline silicon secondary mirror. A
helium-filled balloon carried the FGE to an altitude of 37 km
(Bernasconi et al. 2000, 2001). We select among all the observations a
set of high spatial and temporal resolution observations of an emerging
active region with numerous Ellerman bombs (EBs). Statistical and
morphology analysis have been performed. We demonstrate that Ellerman
bombs are the result of magnetic reconnection in the low chromosphere
by a magnetic topology analysis. The loci of EBs coincide with "bald
patches" (BPs). BPs are regions where the vector field is tangential to
the boundary (photosphere) along an inversion line. We conclude that
emerging flux through the photosphere is achieved through resistive
emergence of U loops connecting small Ω loops before rising in the
chromosphere and forming Arch Filament System (AFS).

---------------------------------------------------------
Title: Statistics, morphology, and energetics of Ellerman bombs
Authors: Georgoulis, Manolis K.; Rust, David M.; Bernasconi, Pietro
N.; Schmieder, Brigitte
2002ESASP.505..125G Altcode: 2002IAUCo.188..125G; 2002solm.conf..125G
We have performed a detailed analysis of several hundreds Hα Ellerman
bombs in the low chromosphere, above an emerging flux region. We
find that Ellerman bombs may be small-scale, low-altitude, magnetic
reconnection events that heat the low chromosphere in the active
region. Their energy content varies between 1027 erg and
1028 erg, typical of sub-flaring activity.

---------------------------------------------------------
Title: The Near-Infrared Chromosphere Observatory
Authors: Rust, David M.; Bernasconi, Pietro N.; Labonte, Barry J.;
Georgoulis, Manolis K.; Fox, Nicola J.; Kalkofen, Wolfgang; Lin,
Haoseng
2002ESASP.505..561R Altcode: 2002IAUCo.188..561R; 2002solm.conf..561R
The Near-Infrared Chromosphere Observatory (NICO) is a proposed
balloon-borne observatory aiming to investigate the magnetic structure
and the sources of heating in the solar chromosphere. NICO will be based
on the successful Flare Genesis Experiment (FGE), a pioneer in applying
novel technologies for the study of the Sun. NICO will map magnetic
fields, velocity fields, and heating events in the chromosphere with
unprecedented quality.

---------------------------------------------------------
Title: Vector magnetic field observations of flux tube emergence
Authors: Schmieder, B.; Aulanier, G.; Pariat, E.; Georgoulis, M. K.;
Rust, D. M.; Bernasconi, P. N.
2002ESASP.505..575S Altcode: 2002IAUCo.188..575S; 2002solm.conf..575S
With Flare Genesis Experiment (FGE), a balloon borne Observatory high
spatial and temporal resolution vector magnetograms have been obtained
in an emerging active region. The comparison of the observations
(FGE and TRACE) with a linear force-free field analysis of the region
shows where the region is non-force-free. An analysis of the magnetic
topology furnishes insights into the existence of "bald patches"
regions (BPs are regions where the vector field is tangential to the
boundary (photosphere) along an inversion line). Magnetic reconnection
is possible and local heating of the chromopshere is predicted near the
BPs. Ellerman bombs (EBs) were found to coincide with few BPs computed
from a linear force-free extrapolation of the observed longitudinal
field. But when the actual observations of transverse fields were used
to identify BPs, then the correspondence with EB positions improved
significantly. We conclude that linear force-free extrapolations must
be done with the true observed vertical fields, which require the
measurement of the three components of the magnetic field.

---------------------------------------------------------
Title: Moving Dipolar Features in an Emerging Flux Region
Authors: Bernasconi, P. N.; Rust, D. M.; Georgoulis, M. K.; Labonte,
B. J.
2002SoPh..209..119B Altcode:
On 25 January, 2000, we observed active region NOAA 8844 with the
Flare Genesis Experiment (FGE), a balloon-borne observatory with an
80-cm solar telescope. FGE was equipped with a vector polarimeter and
a tunable Fabry-Pérot narrow-band filter. It recorded time series of
filtergrams, vector magnetograms and Dopplergrams at the Ca i 6122.2 Å
line, and Hα filtergrams with a cadence between 2.5 and 7.5 min. At
the time of the observations, NOAA 8844 was located at approximately
5° N 30° W. The region was growing rapidly; new magnetic flux was
constantly emerging in three supergranules near its center. We report on
the structure and behavior of peculiar moving dipolar features (MDFs)
in the emerging flux, and we describe in detail how the FGE data were
analyzed. In longitudinal magnetograms, the MDFs appeared to be small
dipoles flowing into sunspots and supergranule boundaries. Previously,
dipolar moving magnetic features (MMFs) have only been observed
flowing out from sunspots. The FGE vector magnetograms show that the
MDFs occurred in a region with nearly horizontal fields, the MDFs
being distinguished as undulations in these fields. We identify the
MDFs as stitches where the emerging flux ropes were still tied to the
photosphere by trapped mass. We present a U-loop model that accounts for
their unusual structure and behavior, as well as showing how emerging
flux sheds entrained mass.

---------------------------------------------------------
Title: Statistics, Morphology, and Energetics of Ellerman Bombs
Authors: Georgoulis, Manolis K.; Rust, David M.; Bernasconi, Pietro
N.; Schmieder, Brigitte
2002ApJ...575..506G Altcode:
We investigate the statistical properties of Ellerman bombs in the
dynamic emerging flux region NOAA Active Region 8844, underneath
an expanding arch filament system. High-resolution chromospheric
Hα filtergrams (spatial resolution 0.8"), as well as photospheric
vector magnetograms (spatial resolution 0.5") and Dopplergrams, have
been acquired by the balloon-borne Flare Genesis Experiment. Hα
observations reveal the first “seeing-free” data set on Ellerman
bombs and one of the largest samples of these events. We find that
Ellerman bombs occur and recur in preferential locations in the low
chromosphere, either above or in the absence of photospheric neutral
magnetic lines. Ellerman bombs are associated with photospheric
downflows, and their loci follow the transverse mass flows on the
photosphere. They are small-scale events, with typical size 1.8"×1.1"
, but this size depends on the instrumental resolution. A large number
of Ellerman bombs are probably undetected, owing to limited spatial
resolution. Ellerman bombs occur in clusters that exhibit fractal
properties. The fractal dimension, with an average value ~1.4, does
not change significantly in the course of time. Typical parameters
of Ellerman bombs are interrelated and obey power-law distribution
functions, as in the case of flaring and subflaring activity. We find
that Ellerman bombs may occur on separatrix, or quasi-separatrix,
layers, in the low chromosphere. A plausible triggering mechanism
of Ellerman bombs is stochastic magnetic reconnection caused by the
turbulent evolution of the low-lying magnetic fields and the continuous
reshaping of separatrix layers. The total energies of Ellerman bombs
are estimated in the range (1027, 1028) ergs, the
temperature enhancement in the radiating volume is ~2×103
K, and the timescale of radiative cooling is short, of the order of
a few seconds. The distribution function of the energies of Ellerman
bombs exhibits a power-law shape with an index ~-2.1. This suggests
that Ellerman bombs may contribute significantly to the heating of
the low chromosphere in emerging flux regions.

---------------------------------------------------------
Title: The Near-Infrared Chromosphere Observatory (NICO)
Authors: Rust, D. M.; Bernasconi, P. N.; LaBonte, B. J.; Georgoulis,
M. K.; Kalkofen, W.; Fox, N. J.; Lin, H.
2002AAS...200.3902R Altcode: 2002BAAS...34..701R
NICO is a proposed cost-effective platform for determining the magnetic
structure and sources of heating for the solar chromosphere. It is a
balloon-borne observatory that will use the largest solar telescope
flying and very high data rates to map the magnetic fields, velocities,
and heating events of the chromosphere and photosphere in unprecedented
detail. NICO is based on the Flare Genesis Experiment (FGE), which
has pioneered in the application of technologies important to NASA's
flight program. NICO will also introduce new technologies, such
as wavefront sensing for monitoring telescope alignment; real-time
correlation tracking and high-speed image motion compensation for
smear-free imaging; and wide aperture Fabry-Perot filters for extended
spectral scanning. The telescope is a classic Cassegrain design with
an 80-cm diameter F/1.5 primary mirror made of Ultra-Low-Expansion
glass. The telescope structure is graphite-epoxy for lightweight,
temperature-insensitive support. The primary and secondary mirror
surfaces are coated with silver to reflect more than 97% of the incident
solar energy. The secondary is made of single-crystal silicon, which
provides excellent thermal conduction from the mirror surface to its
mount, with negligible thermal distortion. A third mirror acts as a
heat dump. It passes the light from a 15-mm diameter aperture in its
center, corresponding to a 322"-diameter circle on the solar surface,
while the rest of the solar radiation is reflected back out of the
front of the telescope. The telescope supplies the selected segment
of the solar image to a polarization and spectral analysis package
that operates with an image cadence 1 filtergram/sec. On-board data
storage is 3.2 Terabytes. Quick-look images will be sent in near real
time to the ground via the TDRSS communications link.

---------------------------------------------------------
Title: Photospheric Vertical Current Density and Overlying Atmospheric
Activity in an Emerging Flux Region
Authors: Georgoulis, M. K.; Rust, D. M.; Bernasconi, P. N.;
Schmieder, B.
2002AAS...200.2004G Altcode: 2002BAAS...34..673G
Using high-resolution vector magnetograms obtained by the balloon-borne
Flare Genesis Experiment (FGE), we construct maps of the vertical
current density in the emerging flux region NOAA 8844. The vertical
current density has been decomposed into components that are
field-aligned and perpendicular to the magnetic field, thus allowing
a straightforward identification of force-free areas, as well as of
areas where the force-free approximation breaks down. Small-scale
chromospheric activity, such as H α Ellerman bombs and Ultraviolet
bright points in 1600 Åshow a remarkable correlation with areas of
strong current density. Simultaneous data of overlying coronal loops,
observed by TRACE in the Extreme Ultraviolet (171 Åand 195 Å), have
been carefully co-aligned with the FGE photospheric maps. We find
that the footpoints of the TRACE loops always coincide with strong
vertical currents and enhancements of the current helicity density. We
also investigate whether the force-free approximation is valid on the
photosphere during various evolutionary stages of the active region.

---------------------------------------------------------
Title: Investigation of the Sources of Irradiance Variation on the
Sun (ISIS)
Authors: LaBonte, B. J.; Bernasconi, P. N.; Rust, D.; Foukal, P.;
Hudson, H.; Spruit, H.
2002AAS...200.5608L Altcode: 2002BAAS...34..736L
There is a persistent correlation of the longterm climate change and
solar irradiance. ISIS is designed to understand the physical basis of
this correlation. ISIS combines an innovative bolometric imager and a
multiband CCD imager. The bolometric imager has uniform response from
200 nm to 3000 nm, spatial resolution &lt; 5 arcseconds, and precision
of &lt; 0.1% in a one minute integration. The multiband imager records
ultraviolet irradiance variation in the band from 200 to 350 nm,
measures photospheric temperature structure, and provides chromospheric
structure in Ca II K and H-alpha, with spatial resolution &lt;1.0
arcsecond. Designed for flight on the Solar Dynamics Observatory,
ISIS will provide the comprehensive photometric measurements needed
to characterize the irradiance variation from identifiable structures
and challenge theoretical models of convection and the solar dynamo.

---------------------------------------------------------
Title: The Solar Bolometric Imager
Authors: Bernasconi, P. N.; Foukal, P.; Rust, D. M.
2002AAS...200.5605B Altcode: 2002BAAS...34R.735B
The Solar Bolometric Imager (SBI) is an innovative solar telescope
capable of recording images in essentially total photospheric light,
with an angular resolution of 5", sufficient to distinguish sunspots,
faculae and enhanced network. These are the photospheric magnetic
structures so far linked most closely to irradiance variation. The
balloon-borne SBI will provide the first bolometric maps of the
photosphere, to evaluate the photometric contribution of magnetic
structures more accurately than has been achievable so far, using
spectrally selective imaging over restricted wavebands. More accurate
removal of the magnetic feature contribution will enable us to determine
whether other solar irradiance mechanisms exist besides the effects
of photospheric magnetism. The SBI detector is an array of 320 X 240
ferro-electric thermal IR elements whose spectral absorptance has
been extended and flattened by a deposited layer of gold-black. The
telescope itself is a 30-cm Dall-Kirkham design with uncoated primary
and secondary pyrex mirrors. The combination of telescope and bolometric
array provides an image of the solar irradiance with a flat spectral
response between 0.28 um and 2.6 um, over a field of view of 15.2' X
11.4', and a pixel size of 2.8". After a successful set of ground-based
tests, the instrument is being readied for a one-day stratospheric
balloon flight that will take place in September 2003. The observing
platform will be the gondola previously used for the Flare Genesis
Experiment project (FGE), retrofitted to house and control the SBI
telescope and detector. The balloon flight will enable SBI to image over
essentially the full spectral range accepted by non-imaging space borne
radiometers such as ACRIM, making the data sets complementary. The SBI
flight will also provide important engineering data to validate the
space worthiness of the novel gold-blackened thermal array detectors,
and verify the thermal performance of the SBI's uncoated optics in a
vacuum environment. This work was funded by NASA under grant NAG5-10998.

---------------------------------------------------------
Title: An Automated System for Detecting Sigmoids in Solar X-ray
Images
Authors: LaBonte, B. J.; Rust, D. M.; Bernasconi, P. N.
2002AGUSMSH52A..02L Altcode:
The probability of a coronal mass ejection (CME) occurring is linked
to the appearance of structures, called sigmoids, in satellite X-ray
images of the sun. By examination of near real time images, we can
detect sigmoids visually and estimate the probability of a CME and
the probability that it will cause a major geomagnetic storm. We have
devised a pattern recognition system to detect the sigmoids in Yohkoh
and GOES (when available) X-ray images automatically. When implemented
in a near real time environment, this system should allow long term,
3 - 7 day, forecasts of CMEs and their potential for causing major
geomagnetic storms.

---------------------------------------------------------
Title: The solar bolometric imager
Authors: Rust, D.; Bernasconi, P.; Foukal, P.
2002cosp...34E1200R Altcode: 2002cosp.meetE1200R
The balloon-borne Solar Bolometric Imager (SBI) will provide the
first bolometric (integrated light) maps of the photosphere, to
evaluate the photometric contribution of magnetic structures more
accurately than has been achievable with spectrally selective imaging
over restricted wavebands. More accurate removal of the magnetic
feature contribution will enable us to determine if solar irradiance
variation mechanisms exist other than the effects of photospheric
magnetism. The SBI detector is an array of 320 x 240 ferro -electric
thermal IR elements whose spectral absorptance has been extended and
flattened by a deposited layer of gold- black. The telescope itself is
a 30-cm Dall-Kirkham design with uncoated primary and secondary pyrex
mirrors. The combination of telescope and bolometric array provides
an image of the sun with a flat spectral response between 0.28 microns
and 2.6 microns, over a field of view of 15.2 x 11.4 min, and a pixel
size of 2.8 arcsec. After a successful set of ground-based tests, the
instrument is being readied for a one-day stratospheric balloon flight
that will take place in September 2003. The observing platform will be
the gondola previously used for the Flare Genesis Experiment (FGE),
retrofitted to house and control the SBI telescope and detector. The
balloon flight will enable SBI to image over essentially the full
spectral range accepted by non-imaging space-borne radiometers such
as ACRIM, making the data sets complementary. The SBI flight will also
provide important engineering data to validate the space worthiness of
the novel gold-blackened thermal array detectors, and verify the thermal
performance of the SBI's uncoated optics in a vacuum environment. This
work was funded by NASA under grant NAG5-10998.

---------------------------------------------------------
Title: Sunspot Formation from Emerging Flux Ropes - Observations
from Flare Genesis
Authors: Rust, D. M.; Bernasconi, P. N.; Georgoulis, M. K.; LaBonte,
B. J.; Schmieder, B.
2001AGUSM..SP42A09R Altcode:
From January 10 to 27, 2000, the Flare Genesis payload observed
the Sun while suspended from a balloon in the stratosphere above
Antarctica. The goal of the mission was to acquire a long time series of
high-resolution images and vector magnetograms of the solar photosphere
and chromosphere. We obtained images, magnetograms and Dopplergrams
in the magnetically sensitive Ca I line at 6122 Angstroms. Additional
simultaneous images were obtained in the wing of H-alpha. On January
25, 2000, we observed in NOAA region 8844 at N05 W30. The rapid
development of a sunspot group that apparently included a delta spot
(two polarities within one umbra). We considered a variety of models
for interpreting these observations, including a twisted flux tube,
a bipole that annihilates, a bipole that submerges, and a field
distorted by mass loading. From the vector magnetograms and Doppler
measurements, we conclude that nearly horizontal flux ropes are swept
into the developing spot where they tilt upward to contribute to the
familiar nearly vertical sunspot fields. The largest flux rope exhibited
a twisted structure, and its angle with respect to the vertical was so
great that it could be mistaken for a positive magnetic field merging
into a negative sunspot. Flare Genesis was supported by NASA grant
NAG5-8331 and by NSF grant OPP-9909167.

---------------------------------------------------------
Title: Ellerman Bombs in a Solar Active Region: Statistical Properties
and Implications
Authors: Georgoulis, M. K.; Rust, D. M.; Bernasconi, P. N.
2001AGUSM..SP52B05G Altcode:
We have embedded the concept of Self-Organized Criticality (SOC) in
deterministic Cellular Automata (CA) models in an attempt to simulate
the emergence of flaring and sub-flaring activity in solar active
regions. SOC CA models reproduce reasonably well several aspects of the
statistical properties of flares and, moreover, they allow predictions
regarding the respective properties of the unresolved nanoflares. We
compare the above-mentioned predictions with observed arcsecond and
sub-arcsecond activity on the low-chromosphere, in a newly formed active
region. The source of the observations is the Flare Genesis Experiment
(FGE) which has provided us with high-resolution maps of the magnetic
field and the velocity field vectors on the photospheric boundary, as
well as Hα filtergrams on the low-chromosphere. Moreover, UV and EUV
data from TRACE are used for determining the activity on the overlying
atmospheric layers. We present preliminary results on the statistical
properties of transient Hα brightenings (Ellerman Bombs) which
correlate well with significant overlying UV emission. Implications
of these results, as well as potential directions for modeling the
low-lying activity in the solar atmosphere are discussed. This work
was sponsored by NASA grant NAG5-8331 and NSF grant OPP-9909162

---------------------------------------------------------
Title: Peculiar Moving Magnetic Features Observed With the Flare
Genesis Experiment
Authors: Bernasconi, P. N.; Rust, D. M.; Georgoulis, M. K.; LaBonte,
B. J.; Schmieder, B.
2001AGUSM..SP51A02B Altcode:
With the Flare Genesis Experiment (FGE), a balloon-borne 80-cm solar
telescope, we observed the active region NOAA 8844 on January 25,
2000 for several hours. FGE was equipped with a vector polarimeter
and a lithium-niobate Fabry-Perot narrow-band filter. It recorded
time series of filtergrams, vector magnetograms, and dopplergrams
at the CaI 6122.2 Angstroms line, as well as Hα filtergrams, with a
cadence between 2.5 and 7.5 minutes. At the time of the observations
NOAA 8844 was located at approximately 5 deg N, 30 deg W. It was a new
flux emergence that first appeared on the solar disk two days before
and was still showing a very dynamic behavior. Its two main polarity
parts were rapidly moving away from each other and new magnetic flux
was constantly emerging from its center. Here we describe the structure
and behavior of peculiar small moving magnetic dipoles (called moving
magnetic features MMF's) that we observed near the trailing negative
polarity sunspot of NOAA 8844. Presentations by D. M. Rust, and by
M. K. Georgoulis at this meeting will focus on other aspects of the
same active region. The MMF's took the form of small dipoles that first
emerged into the photosphere near the center of a supergranular cell
located next to the main trailing flux concentration. They rapidly
migrated towards the spot, following the supergranular flow. The two
polarities of the little dipoles did not separate; they moved together
with same speed and in the same direction. The dipoles were oriented
parallel to their motion toward the negative spot, with the positive
polarity always leading. MMF's usually move away from sunspots, and
their orientation is the reverse of what we see here. In addition,
we noted that the dipole structure was not symmetric. The field lines
of the trailing part of the MMF's (negative polarity) were always
much more perpendicular to the local horizontal than the ones of the
leading part. The trailing part looked more compact and circular, while
the leading part was more elongated in the direction of the motion. We
conclude that we observed a new type of MMF's with a totally different
magnetic structure than previously seen. We present a possible model
that could explain their unusual structure and behavior. This work
was supported by NASA grant NAG5-8331 and NSF grant OPP-9909167.

---------------------------------------------------------
Title: High Resolution Vector Magnetograms with the Flare Genesis
Vector Polarimeter
Authors: Bernasconi, P. N.; Rust, D. M.; Eaton, H. A. C.
2001ASPC..236..399B Altcode: 2001aspt.conf..399B
No abstract at ADS

---------------------------------------------------------
Title: Balloon-borne telescope for high-resolution solar imaging
and polarimetry
Authors: Bernasconi, Pietro N.; Rust, David M.; Eaton, Harry A.;
Murphy, Graham A.
2000SPIE.4014..214B Altcode:
In January 2000, an 80-cm F/1.5 Ritchey-Chretien solar telescope
flew for 17 days suspended from a balloon in the stratosphere above
Antarctica. The goal was to acquire long time series of high spatial
resolution images and vector- magnetograms of the solar photosphere
and chromosphere. Such observations will help to advance our basic
scientific understanding of solar activity, in particular flares. Flying
well above the turbulent layers of the Earth's atmosphere, the telescope
should be able to operate close to its diffraction limited resolution
of 0.2 arcsec, providing high resolution observations of small scale
solar features. To achieve this goal we developed a platform for the
optical telescope that is stable to nearly 10 arcsec. We also developed
an image motion compensation system that stabilizes the solar image
on the CCD focal plane to about 1 arcsec.

---------------------------------------------------------
Title: New Results from the Flare Genesis Experiment
Authors: Rust, D. M.; Bernasconi, P. N.; Eaton, H. A.; Keller, C.;
Murphy, G. A.; Schmieder, B.
2000SPD....31.0302R Altcode: 2000BAAS...32..834R
From January 10 to 27, 2000, the Flare Genesis solar telescope
observed the Sun while suspended from a balloon in the stratosphere
above Antarctica. The goal of the mission was to acquire long time
series of high-resolution images and vector magnetograms of the
solar photosphere and chromosphere. Images were obtained in the
magnetically sensitive Ca I line at 6122 Angstroms and at H-alpha
(6563 Angstroms). The FGE data were obtained in the context of Max
Millennium Observing Campaign #004, the objective of which was to study
the “Genesis of Solar Flares and Active Filaments/Sigmoids." Flare
Genesis obtained about 26,000 usable images on the 8 targeted active
regions. A preliminary examination reveals a good sequence on an
emerging flux region and data on the M1 flare on January 22, as well
as a number of sequences on active filaments. We will present the
results of our first analysis efforts. Flare Genesis was supported
by NASA grants NAG5-4955, NAG5-5139, and NAG5-8331 and by NSF grant
OPP-9615073. The Air Force Office of Scientific Research and the
Ballistic Missile Defense Organization supported early development of
the Flare Genesis Experiment.

---------------------------------------------------------
Title: Design and Performance of the Flare Genesis Experiment
Authors: Bernasconi, P. N.; Rust, D. M.; Eaton, H. A.; Murphy, G. A.
2000SPD....31.0289B Altcode: 2000BAAS...32..826B
In January 2000, an 80-cm F/1.5 Ritchey-Chretien solar telescope
flew for18 days suspended from a balloon in the stratosphere above
Antarctica. The goal of the flight was to acquire long time series of
high-resolution images and vector magnetograms of the solar photosphere
and chromosphere. Such observations will help to advance our basic
scientific understanding of solar activity, in particular, flares and
coronal mass ejections. Flying well above the turbulent layers of
the Earth's atmosphere, the telescope obtained unprecedented sharp
and stable observations of small-scale solar features. To achieve
this goal we developed a platform for the optical telescope that is
stable to nearly 10 arcsec. In addition, we developed an image motion
compensation system that stabilizes the solar image on the focal
plane to about 1 arcsec. When the payload was in line of sight with
the ground station, communications were accomplished via a low-speed
radio link for sending commands and receiving telemetry and a high-speed
downlink for receiving images. During the rest of the flight, contact
with the payload was sporadic and only instrument status could be
telemetered down. After the flight, the data were recovered from
on-board tapes. This presentation will focus on the description of
the instrument and its operating principle. Preliminary results from
the January 2000 flight will be presented in a companion paper.

---------------------------------------------------------
Title: Grids of stellar models. VIII. From 0.4 to 1.0
{Msun} at Z=0.020 and Z=0.001, with the MHD equation
of state
Authors: Charbonnel, C.; Däppen, W.; Schaerer, D.; Bernasconi, P. A.;
Maeder, A.; Meynet, G.; Mowlavi, N.
1999A&AS..135..405C Altcode: 1998astro.ph.10416C
We present stellar evolutionary models covering the mass range from 0.4
to 1 Msun calculated for metallicities Z=0.020 and 0.001
with the MHD equation of state \cite[(Hummer &amp; Mihalas 1988;]
\cite[Mihalas et al. 1988;] \cite[Däppen et al. 1988).] A parallel
calculation using the OPAL \cite[(Rogers et al. 1996)] equation of
state has been made to demonstrate the adequacy of the MHD equation of
state in the range of 1.0 to 0.8 Msun (the lower end of the
OPAL tables). Below, down to 0.4 Msun, we have justified
the use of the MHD equation of state by theoretical arguments and the
findings of \cite[Chabrier &amp; Baraffe (1997).] We use the radiative
opacities by \cite[Iglesias &amp; Rogers (1996),] completed with the
atomic and molecular opacities by \cite[Alexander &amp; Fergusson
(1994).] We follow the evolution from the Hayashi fully convective
configuration up to the red giant tip for the most massive stars,
and up to an age of 20 Gyr for the less massive ones. We compare our
solar-metallicity models with recent models computed by other groups and
with observations. The present stellar models complete the set of grids
computed with the same up-to-date input physics by the Geneva group
(Z=0.020 and 0.001, \cite[Schaller et al. 1992;] \cite[Bernasconi 1996,]
and \cite[Charbonnel et al. 1996;] Z=0.008, \cite[Schaerer et al. 1992;]
Z=0.004, \cite[Charbonnel et al. 1993;] Z=0.040, \cite[Schaerer et
al. 1993;] Z=0.10, \cite[Mowlavi et al. 1998;] enhanced mass loss
rate evolutionary tracks, \cite[Meynet et al. 1994).] Data available
at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5)
or via http://cdsweb.u-strasbg.fr/Abstract.html

---------------------------------------------------------
Title: High Resolution polarimetry with a Balloon-Borne Telescope:
The Flare Genesis Experiment
Authors: Bernasconi, P.; Rust, D.; Murphy, G.; Eaton, H.
1999ASPC..183..279B Altcode: 1999hrsp.conf..279B
No abstract at ADS

---------------------------------------------------------
Title: VizieR Online Data Catalog: Grids of stellar
models. VIII. (Charbonnel+ 1999)
Authors: Charbonnel, C.; Dappen, W.; Schaerer, D.; Bernasconi, P. A.;
Maeder, A.; Meynet, G.; Mowlavi, N.
1998yCat..41350405C Altcode:
We present stellar evolutionary models covering the mass range
from 0.4 to 1M⊙ calculated for metallicities Z=0.020
and 0.001 with the MHD equation of state (Hummer &amp; Mihalas,
1988ApJ...331..794H, Mihalas et al., 1988ApJ...331..815M, Daeppen
et al., 1988ApJ...332..261D). A parallel calculation using the OPAL
(Rogers et al., 1996ApJ...456..902R) equation of state has been made to
demonstrate the adequacy of the MHD equation of state in the range of
1.0 to 0.8M⊙ (the lower end of the OPAL tables). Below,
down to 0.4M⊙, we have justified the use of the MHD
equation of state by theoretical arguments and the findings of
Chabrier &amp; Baraffe (1997A&amp;A...327.1039C). We use the radiative
opacities by Iglesias &amp; Rogers (1996ApJ...464..943I), completed
with the atomic and molecular opacities by Alexander &amp; Fergusson
(1994ApJ...437..879A). We follow the evolution from the Hayashi fully
convective configuration up to the redgiant tip for the most massive
stars, and up to an age of 20Gyr for the less massive ones. We compare
our solar-metallicity models with recent models computed by other
groups and with observations. (21 data files).

---------------------------------------------------------
Title: Grids of stellar models. VII. From 0.8 to 60 M_\odot at Z
= 0.10
Authors: Mowlavi, N.; Schaerer, D.; Meynet, G.; Bernasconi, P. A.;
Charbonnel, C.; Maeder, A.
1998A&AS..128..471M Altcode:
We present a new grid of stellar models from 0.8 to \massii{60}
at Z=0.10, with mass loss and moderate overshooting, from the zero
age main sequence to either the helium flash (low mass stars),
the early AGB phase (intermediate-mass stars) or the end of carbon
burning (massive stars). The calculations are done with opacities
provided by \cite[Iglesias &amp; Rogers (1993)]{igl93}, completed
by those of \cite[Alexander &amp; Ferguson (1994)]{ale94} at low
temperatures. This grid is a homogeneous extension to very high
metallicity of the previous grids published by the Geneva group. It
is useful for the study of galactic bulges, elliptical galaxies and
eventually quasars. Calculations of stars more massive than \massii{60}
are not presented as these objects lose almost their entire mass during
their main sequence phase, and are likely to end their life as white
dwarfs. Data available at the CDS via anonymous ftp 130.79.128.5 or
via http://cdsweb.u-strasbg.fr/Abstract.html

---------------------------------------------------------
Title: Complex magnetic fields in an active region
Authors: Bernasconi, P. N.; Keller, C. U.; Solanki, S. K.; Stenflo,
J. O.
1998A&A...329..704B Altcode:
High-resolution observations of the full Stokes vector in Fe\sc i
spectral lines around 5250 Angstroms obtained at the Swedish Vacuum
Solar Telescope on La Palma with the ZIMPOL I Stokes polarimeter in a
complex active region reveal the presence of anomalously shaped Stokes
profiles indicating the coexistence of at least two magnetic components
within the same spatial resolution element. These Stokes profiles have
been analyzed with an inversion code based on a 3-component atmospheric
model with two magnetic and one field-free component. The fits to
the observations in a magnetic region that resembles a small penumbra
reveal the presence of a horizontal magnetic field component with an
average field strength of /line{B}=840 G, a mean filling factor of
/lineα=0.12, and an average temperature /line{T}=5400 K at log {tau_
{5000}}=-1.5 embedded in the main “penumbral” magnetic field that
has /line{B}=1500 G, /lineα=0.56, and /line{T}=4900 K. The horizontal
component exhibits a mean outflow of 2.7 km s(-1) which is mainly due
to the Evershed flow. In a region where there are strong downflows up
to 7 km s(-1) , we infer the possible presence of a shock front whose
height changes along the slit. The height variation can be explained by
a change of the gas pressure at the base of the photosphere below the
shock front as proposed by Thomas &amp; Montesinos (1991). Small plages
with field strengths below 900 G have been observed in the vicinity
of some pores. Finally, we present a puzzling field structure at the
boundary between two adjacent pores. Ambiguous results suggest that
although the inversion code is able to successfully invert even very
complex Stokes profiles, we are far from a complete description of the
field structure in complex magnetic regions. We warn that magnetograms
and fits to data involving only a single magnetic component may hide
the true complexity of the magnetic structure in at least some parts
of active regions.

---------------------------------------------------------
Title: VizieR Online Data Catalog: Grids of stellar
models. VII. (Mowlavi+ 1998)
Authors: Mowlavi, N.; Schaerer, D.; Meynet, G.; Bernasconi, P. A.;
Charbonnel, C. Maeder A.
1997yCat..41280471M Altcode:
We present a new grid of stellar models from 0.8 to 60M⊙&lt;/S
Z=0.10, with mass loss and moderate overshooting, from the zero age main
sequence to either the helium flash (low mass stars), the early AGB
phase (intermediate-mass stars or the end of carbon burning (massive
stars). The calculations are done with opacities provided by Iglesias
&amp; Rogers (1993ApJ...412..752I), completed by those of Alexander
&amp; Ferguson (1994ApJ...437..879A) at low temperatures. This grid is
a homogeneous extension to very high metallicity of the previous grids
published by the Geneva group. It is useful for the study of galactic
bulges, elliptical galaxies and eventually quasars. Calculations of
stars more massive than 60M⊙ are not presented as these
objects lose almost their entire mass during their main sequence
phase, and are likely to end their life as white dwarfs. (19
data files).

---------------------------------------------------------
Title: Geneva photometry in the young open cluster NGC 6231.
Authors: Raboud, D.; Cramer, N.; Bernasconi, P. A.
1997A&A...325..167R Altcode:
We present photoelectric (127 stars) and CCD (168 stars) Geneva
photometry for the very young open cluster NGC 6231. We have searched
for new cluster members out to a distance of ~13['arc], extending
the Seggewiss area (~8['arc]), and we found at least 64 new probable
members in this extended field. Differential reddening is clearly
measured across the cluster area. We determine the cluster distance
(1800 pc) and age (3.8+/-0.6x10^6^yr). The probable presence of PMS
stars and the consequence of this population on the cluster formation
history is analysed. We also found that the O8.5III star S161 is a long
term variable and we present its light curve extending over more than
20 years. Finally we discuss the existence of Ap stars in the cluster.

---------------------------------------------------------
Title: Diffusion in differentially rotating stars.
Authors: Bernasconi, P. A.
1997A&A...323..831B Altcode:
A linear stability analysis of rotating Boussinesq flows including
shear, μ-gradients and radiation losses leads to modification of
the classical Ledoux criterion for convective equilibrium. The role
of shear in spreading the radial extent of the convective layers
is briefly investigated, and we found that some effects may be
expected in the latest nuclear evolutionary stages of massive stars,
whose short timescales and rather steep μ-barriers concur to hinder
angular momentum redistribution within their condensed cores. Also,
semiconvective shear zones (Maeder, 1997A&amp;A...321..134M) are
predicted in those radiative shells where the available shear energy is
not sufficient to completely overturn the stable thermal gradient. We
then provide a prescription to compute a modified diffusion coefficient
for passive scalars in presence of shear and thermal conductivity.

---------------------------------------------------------
Title: VizieR Online Data Catalog: Geneva photometry in NGC 6231
(Raboud+ 1997)
Authors: Raboud, D.; Cramer, N.; Bernasconi, P. A.
1997yCat..33250167R Altcode:
We present photoelectric (127 stars) and CCD (168 stars) Geneva
photometry for the very young open cluster NGC 6231. We have searched
for new cluster members out to a distance of ~13arcmin, extending the
Seggewiss area (~8arcmin), and we found at least 64 new probable members
in this extended field. Differential reddening is clearly measured
across the cluster area. We determine the cluster distance (1800pc)
and age (3.8+/-0.6x106yr). The probable presence of pre-main
sequence stars and the consequence of this population on the cluster
formation history is analysed. We also found that the O8.5III star S161
is a long term variable and we present its light curve extending over
more than 20 years. Finally we discuss the existence of Ap stars in
the cluster. For a description of the Geneva photometric system,
see e.g. (3 data files).

---------------------------------------------------------
Title: Stokes Vector Polarimetry: Observation and Analysis of Solar
Magnetic Fields %J Ph.D. Thesis, ETH, Zürich
Authors: Bernasconi, P. N.
1997PhDT........49B Altcode:
No abstract at ADS

---------------------------------------------------------
Title: Grids of pre-main sequence stellar models. The accretion
scenario at Z=0.001 and Z=0.020.
Authors: Bernasconi, P. A.
1996A&AS..120...57B Altcode:
I present and briefly discuss a new set of pre-main sequence (MS)
evolutionary tracks computed in the framework of the accretion paradigm
for star formation at metallicities Z=0.001 and Z=0.020. Improved
birthlines are obtained from a time-dependent prescription for the
accretion rate. These evolutionary sequences are better suited than the
canonical approach which starts arbitrarily high on a luminous Hayashi
adiabat, to interpret color-magnitude diagrams and ages of young stellar
associations. They also constitute a (both physical and numerical)
self-consistent extension to the post-MS stellar models previously
published by the Geneva group (Schaller et al. 1992A&amp;AS...96..269S).

---------------------------------------------------------
Title: About the absence of a proper zero age main sequence for
massive stars.
Authors: Bernasconi, P. A.; Maeder, A.
1996A&A...307..829B Altcode:
The formation of stars up to 120Msun_ is computed in
the framework of the accretion scenario. For realistic accretion
rates derived from the observed line width in various molecular dark
clouds, the accretion interlude lasts some 2-2.5Myr, and accounts
for an appreciable nuclear evolution during the optically thick MS
life. Several new results are found concerning massive stars at the top
of the MS: 1) A newly formed massive star with M&gt;=40Msun_
at the time it emerges from its parental cloud has already burned
a substantial fraction of its central hydrogen content. 2) As a
consequence, the formal MS lifetime is substantially reduced. 3)
A proper ZAMS does not exist, since at the time it becomes visible,
the star has already evolved towards lower T_eff_. 4) As a result of
previous evolution, the size of the convective core for a given central
H content is reduced by about 5-10%. 5) We find that for realistic
accretion rates applicable to ordinary star forming regions in the
Galaxy and Magellanic Clouds, a truncation of the IMF is naturally
established around 85-150Msun_ where the accretion time
becomes comparable to the hydrogen burning time. 6) Since massive stars
spend a fraction of their H-burning phase in the parental cocoon,
their true number is larger than estimated and the slope of the IMF
is flatter.

---------------------------------------------------------
Title: Inversion of Stokes Vector Profiles in Terms of a 3-Component
Model
Authors: Bernasconi, P. N.; Solanki, S. K.
1996SoPh..164..277B Altcode:
Various spectropolarimetric observations show peculiar Stokes profiles
that reveal the coexistence of at least two magnetic components in
the same resolution element. An example is given by observations of
the full Stokes vector in a complex active region performed with the
ZIMPOL I Stokes polarimeter. In order to deduce the physical parameters
of the observed regions from such measured profiles, we have extended
an existing inversion code, so that it can now fit the data with models
composed of up to three different atmospheric components. Two of these
components are magnetic and may possess different field strengths,
field geometries, temperature stratifications, and velocity fields. The
third component describes the field free atmosphere surrounding the
magnetic features.

---------------------------------------------------------
Title: Optically Thick Main Sequence Evolution for Still Accreting
Massive Stars
Authors: Bernasconi, P. A.
1996rdfs.conf..411B Altcode:
No abstract at ADS

---------------------------------------------------------
Title: Direct measurements of flux tube inclinations in solar plages.
Authors: Bernasconi, P. N.; Keller, C. U.; Povel, H. P.; Stenflo, J. O.
1995A&A...302..533B Altcode:
Observations of the full Stokes vector in three spectral lines
indicate that flux tubes in solar plages have an average inclination
in the photosphere of 14^o^ with respect to the local vertical. Most
flux tubes are inclined in the eastwards direction, i.e., opposite
to the solar rotation. We have recorded the Stokes vector of the
FeI 5247.1A, FeI 5250.2A, and FeI 5250.7A lines in nine different
plages with the polarization-free 20cm Zeiss coronagraph at the Arosa
Astrophysical Observatory of ETH Zuerich. The telescope has been
modified for solar disk observations. The chosen spectral lines are
particularly sensitive to magnetic field strength and temperature. To
determine the field strength and geometry of the flux tubes in the
observed plages we use an inversion code that numerically solves the
radiative transfer equations and derives the emergent Stokes profiles
for one-dimensional model atmospheres consisting of a flux tube and
its surrounding non-magnetic atmosphere. Our results confirm earlier
indirect estimates of the inclination of the magnetic fields in plages.

---------------------------------------------------------
Title: Stokes Profile Asymmetries in Active Regions
Authors: Balasubramaniam, K. S.; Keil, S. L.; Tomczyk, S.; Bernasconi,
P.
1995SPD....26..205B Altcode: 1995BAAS...27..951B
No abstract at ADS

---------------------------------------------------------
Title: Visible and near-infrared polarimetry with LEST.
Authors: Keller, C. U.; Bernasconi, P. N.; Egger, U.; Povel, H. P.;
Steiner, P.; Stenflo, J. O.
1995LFTR...59.....K Altcode:
This document describes the LEST vector polarimeters for the visible
and the near-infrared part of the solar spectrum. After some general
remarks on precise polarimetry with large telescopes, the authors
present the specifications based on scientific reasons and some
general design considerations. The proposed instrument design for the
visible is based on the ZIMPOL II concept. They present two different
concepts for vector polarimetry in the near infrared. One is based
on a beam-splitter system combined with liquid crystal modulators,
while the other is based on the same modulator package as used in the
visible and optical demodulation in the final focus.

---------------------------------------------------------
Title: Visible and Near Infrared Polarimetry with lest
Authors: Keller, C. U.; Bernasconi, P. N.; Egger, U.; Powel, H. P.;
Steiner, P.; Stenflo, J. O.
1995lest.rept....1K Altcode:
No abstract at ADS

---------------------------------------------------------
Title: Observations of Active Region Dynamics: Preflare Flows and
Field Observations
Authors: Keil, Stephen L.; Balasubramaniam, K. S.; Bernasconi, Pietro;
Smaldone, Luigi A.; Cauzzi, Gianna
1994ASPC...68..265K Altcode: 1994sare.conf..265K
No abstract at ADS

---------------------------------------------------------
Title: Direct Measurements of Fluxtube Inclinations in Plages
Authors: Bernasconi, Pietro N.; Keller, Christoph U.; Stenflo, Jan Olof
1994ASPC...68..131B Altcode: 1994sare.conf..131B
No abstract at ADS