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Author name code: barczynski
ADS astronomy entries on 2022-09-14
author:Barczynski, Krzystof
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Title: Spatial distribution of jets in solar active regions
Authors: Odermatt, J.; Barczynski, K.; Harra, L. K.; Schwanitz, C.;
Krucker, S.
2022A&A...665A..29O Altcode: 2022arXiv220709923O
Context. Solar active regions are known to have jets. These jets are
associated with heating and the release of particles into the solar
wind. <BR /> Aims: Our aim is to understand the spatial distribution
of coronal jets within active regions to understand if there is a
preferential location for them to occur. <BR /> Methods: We analysed
five active regions using Solar Dynamics Observatory Atmospheric
Imaging Assembly data over a period of 2-3.5 days when the active
regions were close to disk centre. Each active region had a different
age, magnetic field strength, and topology. We developed a methodology
for determining the position and length of the jets. <BR /> Results:
Jets are observed more frequently at the edges of the active regions
and are more densely located around a strong leading sunspot. The
number of coronal jets for our active regions is dependent on the
age of the active region. The older active regions produce more jets
than younger ones. Jets were observed dominantly at the edges of the
active regions, and not as frequently in the centre. The number of
jets is independent of the average unsigned magnetic field and total
flux density in the whole active region. The jets are located around
the edges of the strong leading sunspot.
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Title: Automatic detection of small-scale EUV brightenings observed
by the Solar Orbiter/EUI
Authors: Alipour, N.; Safari, H.; Verbeeck, C.; Berghmans, D.;
Auchère, F.; Chitta, L. P.; Antolin, P.; Barczynski, K.; Buchlin,
É.; Aznar Cuadrado, R.; Dolla, L.; Georgoulis, M. K.; Gissot, S.;
Harra, L.; Katsiyannis, A. C.; Long, D. M.; Mandal, S.; Parenti,
S.; Podladchikova, O.; Petrova, E.; Soubrié, É.; Schühle, U.;
Schwanitz, C.; Teriaca, L.; West, M. J.; Zhukov, A. N.
2022A&A...663A.128A Altcode: 2022arXiv220404027A
Context. Accurate detections of frequent small-scale extreme ultraviolet
(EUV) brightenings are essential to the investigation of the physical
processes heating the corona. <BR /> Aims: We detected small-scale
brightenings, termed campfires, using their morphological and
intensity structures as observed in coronal EUV imaging observations
for statistical analysis. <BR /> Methods: We applied a method based
on Zernike moments and a support vector machine (SVM) classifier
to automatically identify and track campfires observed by Solar
Orbiter/Extreme Ultraviolet Imager (EUI) and Solar Dynamics Observatory
(SDO)/Atmospheric Imaging Assembly (AIA). <BR /> Results: This method
detected 8678 campfires (with length scales between 400 km and 4000 km)
from a sequence of 50 High Resolution EUV telescope (HRI<SUB>EUV</SUB>)
174 Å images. From 21 near co-temporal AIA images covering the same
field of view as EUI, we found 1131 campfires, 58% of which were
also detected in HRI<SUB>EUV</SUB> images. In contrast, about 16%
of campfires recognized in HRI<SUB>EUV</SUB> were detected by AIA. We
obtain a campfire birthrate of 2 × 10<SUP>−16</SUP> m<SUP>−2</SUP>
s<SUP>−1</SUP>. About 40% of campfires show a duration longer than 5
s, having been observed in at least two HRI<SUB>EUV</SUB> images. We
find that 27% of campfires were found in coronal bright points and
the remaining 73% have occurred out of coronal bright points. We
detected 23 EUI campfires with a duration greater than 245 s. We found
that about 80% of campfires are formed at supergranular boundaries,
and the features with the highest total intensities are generated at
network junctions and intense H I Lyman-α emission regions observed
by EUI/HRI<SUB>Lya</SUB>. The probability distribution functions for
the total intensity, peak intensity, and projected area of campfires
follow a power law behavior with absolute indices between 2 and 3. This
self-similar behavior is a possible signature of self-organization,
or even self-organized criticality, in the campfire formation
process. <P />Supplementary material (S1-S3) is available at <A
href="https://www.aanda.org/10.1051/0004-6361/202243257/olm">https://www.aanda.org</A>
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Title: Stereoscopy of extreme UV quiet Sun brightenings observed by
Solar Orbiter/EUI
Authors: Zhukov, A. N.; Mierla, M.; Auchère, F.; Gissot, S.;
Rodriguez, L.; Soubrié, E.; Thompson, W. T.; Inhester, B.; Nicula, B.;
Antolin, P.; Parenti, S.; Buchlin, É.; Barczynski, K.; Verbeeck, C.;
Kraaikamp, E.; Smith, P. J.; Stegen, K.; Dolla, L.; Harra, L.; Long,
D. M.; Schühle, U.; Podladchikova, O.; Aznar Cuadrado, R.; Teriaca,
L.; Haberreiter, M.; Katsiyannis, A. C.; Rochus, P.; Halain, J. -P.;
Jacques, L.; Berghmans, D.
2021A&A...656A..35Z Altcode: 2021arXiv210902169Z
Context. The three-dimensional fine structure of the solar atmosphere
is still not fully understood as most of the available observations
are taken from a single vantage point. <BR /> Aims: The goal of the
paper is to study the three-dimensional distribution of the small-scale
brightening events ("campfires") discovered in the extreme-UV quiet Sun
by the Extreme Ultraviolet Imager (EUI) aboard Solar Orbiter. <BR />
Methods: We used a first commissioning data set acquired by the EUI's
High Resolution EUV telescope on 30 May 2020 in the 174 Å passband and
we combined it with simultaneous data taken by the Atmospheric Imaging
Assembly (AIA) aboard the Solar Dynamics Observatory in a similar 171
Å passband. The two-pixel spatial resolution of the two telescopes
is 400 km and 880 km, respectively, which is sufficient to identify
the campfires in both data sets. The two spacecraft had an angular
separation of around 31.5° (essentially in heliographic longitude),
which allowed for the three-dimensional reconstruction of the campfire
position. These observations represent the first time that stereoscopy
was achieved for brightenings at such a small scale. Manual and
automatic triangulation methods were used to characterize the campfire
data. <BR /> Results: The height of the campfires is located between
1000 km and 5000 km above the photosphere and we find a good agreement
between the manual and automatic methods. The internal structure of
campfires is mostly unresolved by AIA; however, for a particularly
large campfire, we were able to triangulate a few pixels, which are
all in a narrow range between 2500 and 4500 km. <BR /> Conclusions: We
conclude that the low height of EUI campfires suggests that they belong
to the previously unresolved fine structure of the transition region and
low corona of the quiet Sun. They are probably apexes of small-scale
dynamic loops heated internally to coronal temperatures. This work
demonstrates that high-resolution stereoscopy of structures in the
solar atmosphere has become feasible.
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Title: Stereoscopic measurements of coronal Doppler velocities
Authors: Podladchikova, O.; Harra, L.; Barczynski, K.; Mandrini,
C. H.; Auchère, F.; Berghmans, D.; Buchlin, É.; Dolla, L.; Mierla,
M.; Parenti, S.; Rodriguez, L.
2021A&A...655A..57P Altcode: 2021arXiv210802280P
Context. The Solar Orbiter mission, with an orbit outside the Sun-Earth
line and leaving the ecliptic plane, opens up opportunities for
the combined analysis of measurements obtained by solar imagers and
spectrometers. For the first time different space spectrometers will be
located at wide angles to each other, allowing three-dimensional (3D)
spectroscopy of the solar atmosphere. <BR /> Aims: The aim of this
work is to prepare a methodology to facilitate the reconstruction
of 3D vector velocities from two stereoscopic line of sight (LOS)
Doppler velocity measurements using the Spectral Imaging of the
Coronal Environment (SPICE) on board the Solar Orbiter and the
near-Earth spectrometers, while widely separated in space. <BR />
Methods: We developed the methodology using the libraries designed
earlier for the STEREO mission, but applied to spectroscopic data
from the Hinode mission and the Solar Dynamics Observatory. We used
well-known methods of static and dynamic solar rotation stereoscopy and
the methods of extreme ultraviolet (EUV) stereoscopic triangulation
for optically thin coronal EUV plasma emissions. We developed new
algorithms using analytical geometry in space to determine the 3D
velocity in coronal loops. <BR /> Results: We demonstrate our approach
with the reconstruction of 3D velocity vectors in plasma flows along
`open' and `closed' magnetic loops. This technique will be applied
to an actual situation of two spacecraft at different separations
with spectrometers on board during the Solar Orbiter nominal phase:
SPICE versus the Interface Region Imaging Spectrograph (IRIS) and
Hinode imaging spectrometer. We summarise how these observations can
be coordinated. <P />Movies associated to Fig. 1 are available at <A
href="https://www.aanda.org/10.1051/0004-6361/202140457/olm">https://www.aanda.org</A>
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Title: Solar prominence diagnostics from non-LTE modelling of Mg II
h&k line profiles
Authors: Peat, A. W.; Labrosse, N.; Schmieder, B.; Barczynski, K.
2021A&A...653A...5P Altcode: 2021arXiv210610351P
<BR /> Aims: We investigate a new method to for obtaining the plasma
parameters of solar prominences observed in the Mg II h&k spectral
lines by comparing line profiles from the IRIS satellite to a bank
of profiles computed with a one-dimensional non-local thermodynamic
equilibrium (non-LTE) radiative transfer code. <BR /> Methods: Using a
grid of 1007 one-dimensional non-LTE radiative transfer models, some
including a prominence-corona transition region (PCTR), we carry out
this new method to match computed spectra to observed line profiles
while accounting for line core shifts not present in the models. The
prominence observations were carried out by the IRIS satellite on 19
April 2018. <BR /> Results: The prominence is very dynamic with many
flows, including a large arm extending from the main body seen near the
end of the observation. This flow is found to be redshifted, as is the
prominence overall. The models are able to recover satisfactory matches
in areas of the prominence where single line profiles are observed. We
recover: mean temperatures of 6000-50 000 K; mean pressures of 0.01-0.5
dyne cm<SUP>−2</SUP>; column masses of 3.7 × 10<SUP>−8</SUP>-5
× 10<SUP>−4</SUP> g cm<SUP>−2</SUP>; a mean electron density
of 7.3 × 10<SUP>8</SUP>-1.8 × 10<SUP>11</SUP> cm<SUP>−3</SUP>;
and an ionisation degree n<SUB>HII</SUB>/n<SUB>HI</SUB> = 0.03 −
4500. The highest values for the ionisation degree are found in
areas where the line of sight crosses mostly plasma from the PCTR,
correlating with high mean temperatures and correspondingly no Hα
emission. <BR /> Conclusions: This new method naturally returns
information on how closely the observed and computed profiles match,
allowing the user to identify areas where no satisfactory match between
models and observations can be obtained. The inclusion of the PCTR was
found to be important when fitting models to data as regions where
satisfactory fits were found were more likely to contain a model
encompassing a PCTR. The line core shift can also be recovered from
this new method, and it shows a good qualitative match with that of
the line core shift found by the quantile method. This demonstrates
the effectiveness of the approach to line core shifts in the new
method. <P />Movies associated to Figs. 10 and A.1 are available at <A
href="https://www.aanda.org/10.1051/0004-6361/202140907/olm">https://www.aanda.org</A>
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Title: Vector Velocities Measurements with the Solar Orbiter SPICE
Spectrometer
Authors: Podladchikova, O.; Harra, L.; Barczynski, K.; Mandrini,
C.; Auchère, F.; Berghmans, D.; Buchlin, E.; Dolla, L.; Mierla, M.;
Parenti, S.; Rodriguez, L.
2021AAS...23831312P Altcode:
The Solar Orbiter mission, with an orbit outside the Sun-Earth
line and leaving the ecliptic plane, opens up opportunities for
the combined analysis of measurements obtained by solar imagers and
spectrometers. For the first time, different spectrometers will be
located at wide angles to each other, allowing three-dimensional (3D)
spectroscopy of the solar atmosphere. Here we develop a methodology to
prepare for this kind of analysis, by using data from the Hinode mission
and the Solar Dynamics Observatory, respectively. We employ solar
rotation to simulate measurements of spectrometers with different views
of the solar corona. The resulting data allow us to apply stereoscopic
tie-pointing and triangulation techniques designed for the STEREO
spacecraft pair, and to perform 3D analysis of the Doppler shifts of
a quasi-stationary active region. Our approach allows the accurate
reconstruction of 3D velocity vectors in plasma flows along "open" and
"closed" magnetic loops. This technique will be applied to the actual
situation of two spacecraft at different separations with spectrometers
on board (the Solar Orbiter Spectral Imaging of the Coronal Environment
versus the Interface Region Imaging Spectrograph (IRIS) and Hinode
imaging spectrometer) and we summarise how these observations can be
coordinated to assess vector velocity measurements. This 3D spectroscopy
method will facilitate the understanding of the complex flows that
take place throughout the solar atmosphere.
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Title: The active region source of a type III radio storm observed
by Parker Solar Probe during encounter 2
Authors: Harra, L.; Brooks, D. H.; Bale, S. D.; Mandrini, C. H.;
Barczynski, K.; Sharma, R.; Badman, S. T.; Vargas Domínguez, S.;
Pulupa, M.
2021A&A...650A...7H Altcode: 2021arXiv210204964H
Context. We investigated the source of a type III radio burst storm
during encounter 2 of NASA's Parker Solar Probe (PSP) mission. <BR />
Aims: It was observed that in encounter 2 of NASA's PSP mission there
was a large amount of radio activity and, in particular, a noise storm
of frequent, small type III bursts from 31 March to 6 April 2019. Our
aim is to investigate the source of these small and frequent bursts. <BR
/> Methods: In order to do this, we analysed data from the Hinode EUV
Imaging Spectrometer, PSP FIELDS, and the Solar Dynamics Observatory
Atmospheric Imaging Assembly. We studied the behaviour of active region
12737, whose emergence and evolution coincides with the timing of the
radio noise storm and determined the possible origins of the electron
beams within the active region. To do this, we probed the dynamics,
Doppler velocity, non-thermal velocity, FIP bias, and densities,
and carried out magnetic modelling. <BR /> Results: We demonstrate
that although the active region on the disc produces no significant
flares, its evolution indicates it is a source of the electron beams
causing the radio storm. They most likely originate from the area
at the edge of the active region that shows strong blue-shifted
plasma. We demonstrate that as the active region grows and expands,
the area of the blue-shifted region at the edge increases, which is
also consistent with the increasing area where large-scale or expanding
magnetic field lines from our modelling are anchored. This expansion
is most significant between 1 and 4 April 2019, coinciding with the
onset of the type III storm and the decrease of the individual burst's
peak frequency, indicating that the height at which the peak radiation
is emitted increases as the active region evolves.
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Title: A Comparison of the Active Region Upflow and Core Morphologies
Using Simultaneous Spectroscopic Observations from IRIS and Hinode.
Authors: Barczynski, K.; Harra, L. K.; Kleint, L.; Panos, B.
2020AGUFMSH004..05B Altcode:
The origin of the slow solar wind is still an open issue. It has
been suggested that upflows at the edge of the active region are the
source of the plasma outflow, and therefore contribute to the slow
solar wind . However, the origin and morphology of the upflow region
remain open questions. We investigated how the plasma properties
(flux, Doppler velocity, and non-thermal velocity) change throughout
the solar atmosphere, from the chromosphere via the transition
region to the corona. We compared the upflow region and the core of
an active region. We studied limb-to-limb observation of the active
region (NOAA 12687) obtained between 14th and 25th November 2017. We
analyzed spectroscopic data simultaneously obtained from Hinode/EIS
and IRIS in six wavelengths (MgII, CII, SiIV, FeXII, FeXIII, and
FeXIV). After the high-precision alignment (accuracy of the Hinode
pixel size) of the raster maps, we studied the mutual relation between
the plasma properties for each line, as well as compared the plasma
properties in the close formation temperature lines. To find the most
characteristic spectra, we classified the spectra in each wavelength
using the machine learning technique k-means . We found that the
fluxes of the lines formed in the close temperatures are highly
correlated in the chromosphere via transition region to the corona. In
the corona, the Doppler velocities are well correlated too. Despite
high-correlation between the transition region and coronal fluxes,
the Doppler velocities are independent in our active region. In
coronal lines, the average non-thermal velocity is higher in the
upflow region than the active region core. In the transition region,
the velocities are similar; thus the non-thermal motions are essential
in the coronal upflow. We found several mutual relations between the
plasma parameters in different spectral lines. These relations and
the spectra classification results suggest that the plasma upflow
begins in the solar corona, but the nature of the upflow region can
be determined from the underlying layers.
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Title: Dynamics and Flows in Active Region NOAA12737 that can
contribute to Type III Bursts observed by Parker Solar Probe during
Encounter 2.
Authors: Harra, L.; Brooks, D.; Barczynski, K.; Mandrini, C. H.;
Vargas-Dominguez, S.; Bale, S.; Badman, S. T.; Raouafi, N. E.;
Rouillard, A. P.
2020AGUFMSH0240001H Altcode:
We have analysed solar activity on the Sun during encounter 2 of the
Parker Solar Probe mission. We studied the period from 30<SUP>th</SUP>
March to 4<SUP>th</SUP> April when a small active region (NOAA 12737)
emerged. This active region showed no significant flaring. During this
time period there were however, an increasing number of type III bursts
measured by the FIELDS instrument. We analyse solar data from SDO-AIA,
SDO-HMI and Hinode EIS to determine what the potential sources of
the type III bursts could be, which occur on timescales of tens of
seconds. The active region core shows small brightenings in EUV and
X-ray wavebands, but these are not continuous, and seem unlikely to be
connected. There are magnetic field changes due to the active region
emergence, which occur on timescales of hours rather than seconds. There
are small scale magnetic flux emergences but these are not frequent
enough to be linked to the continuous type III bursts. As the active
region emerges, we track the upflows at the edge of the active region
as they are created and evolve. We show evidence of variations in the
upflows that seem to be the most likely candidates for the sources of
the type III bursts.
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Title: Stereoscopic Measurements of Coronal Doppler Velocities
Authors: Podladchikova, O.; Harra, L. K.; Barczynski, K.; Mandrini,
C. H.; Auchere, F.; Buchlin, E.; Dolla, L.; Mierla, M.; Rodriguez, L.
2020AGUFMSH038..07P Altcode:
The Solar Orbiter mission, whose orbit is outside the Sun-Earth
line, opens up novel opportunities for the combined analysis of
measurements by solar imagers and spectrometers. For the first time
different spectrometers will be located at wide angles with each
other allowing 3D spectroscopy in the solar atmosphere. In order
to develop a methodology for these opportunities we make use of the
Hinode EUV Imaging Spectrometer (EIS) and Atmospheric Imaging Assembly
(AIA) on the Solar Dynamics Observatory (SDO) and by employing solar
rotation we simulate the measurements of two spectrometers that have
different views of solar corona. The resulting data allows us to apply
stereoscopic tie-pointing and triangulation techniques designed for
SECCHI (Sun Earth Connection Coronal and Heliospheric Investigation)
imaging suite on the STEREO (Solar Terrestrial Relations Observatory)
spacecraft pair and perform three-dimensional analysis of Doppler shifts
of quasi-stationary active region. We present a technique that allows
the accurate reconstruction of the 3D velocity vector in plasma flows
along open and closed magnetic loops. This technique will be applied
to the real situation of two spacecraft at different separations with
spectrometers onboard. This will include the Solar Orbiter Spectral
Imaging of the Coronal Environment (SPICE), the Solar Orbiter Extreme
Ultraviolet Imager (EUI),the Interface Region Imaging Spectrograph
(IRIS) and Hinode EIS spectrometers and we summarise how these can be
coordinated. This 3D spectroscopy is a new research domain that will
aid the understanding of the complex flows that take place throughout
the solar atmosphere.
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Title: Emission of solar chromospheric and transition region features
related to the underlying magnetic field
Authors: Barczynski, K.; Peter, H.; Chitta, L. P.; Solanki, S. K.
2018A&A...619A...5B Altcode: 2018arXiv180702372B
Context. The emission of the upper atmosphere of the Sun is closely
related to magnetic field concentrations at the solar surface. <BR />
Aims: It is well established that this relation between chromospheric
emission and magnetic field is nonlinear. Here we investigate
systematically how this relation, characterised by the exponent
of a power-law fit, changes through the atmosphere, from the upper
photosphere through the temperature minimum region and chromosphere
to the transition region. <BR /> Methods: We used spectral maps from
the Interface Region Imaging Spectrograph (IRIS) covering Mg II and
its wings, C II, and Si IV together with magnetograms and UV continuum
images from the Solar Dynamics Observatory. After a careful alignment
of the data we performed a power-law fit for the relation between each
pair of observables and determine the power-law index (or exponent) for
these. This was done for different spatial resolutions and different
features on the Sun. <BR /> Results: While the correlation between
emission and magnetic field drops monotonically with temperature,
the power-law index shows a hockey-stick-type variation: from the
upper photosphere to the temperature-minimum it drops sharply and then
increases through the chromosphere into the transition region. This
is even seen through the features of the Mg II line, this is,
from k1 to k2 and k3. It is irrespective of spatial resolution or
whether we investigate active regions, plage areas, quiet Sun, or
coronal holes. <BR /> Conclusions: In accordance with the general
picture of flux-flux relations from the chromosphere to the corona,
above the temperature minimum the sensitivity of the emission to the
plasma heating increases with temperature. Below the temperature
minimum a different mechanism has to govern the opposite trend of
the power-law index with temperature. We suggest four possibilities,
in other words, a geometric effect of expanding flux tubes filling the
available chromospheric volume, the height of formation of the emitted
radiation, the dependence on wavelength of the intensity-temperature
relationship, and the dependence of the heating of flux tubes on the
magnetic flux density.
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Title: Miniature loops in the solar corona
Authors: Barczynski, K.; Peter, H.; Savage, S. L.
2017A&A...599A.137B Altcode: 2016arXiv161108513B
Context. Magnetic loops filled with hot plasma are the main building
blocks of the solar corona. Usually they have lengths of the order
of the barometric scale height in the corona that is 50 Mm. <BR />
Aims: Previously it has been suggested that miniature versions of hot
loops exist. These would have lengths of only 1 Mm barely protruding
from the chromosphere and spanning across just one granule in the
photosphere. Such short loops are well established at transition
region temperatures (0.1 MK), and we investigate if such miniature
loops also exist at coronal temperatures (>1 MK). <BR /> Methods:
We used extreme UV (EUV) imaging observations from the High-resolution
Coronal Imager (Hi-C) at an unprecedented spatial resolution of 0.3”
to 0.4”. Together with EUV imaging and magnetogram data from the Solar
Dynamics Observatory (SDO) and X-Ray Telescope (XRT) data from Hinode
we investigated the spatial, temporal and thermal evolution of small
loop-like structures in the solar corona above a plage region close to
an active region and compared this to a moss area within the active
region. <BR /> Results: We find that the size, motion and temporal
evolution of the loop-like features are consistent with photospheric
motions, suggesting a close connection to the photospheric magnetic
field. Aligned magnetograms show that one of their endpoints is rooted
at a magnetic concentration. Their thermal structure, as revealed
together with the X-ray observations, shows significant differences
to moss-like features. <BR /> Conclusions: Considering different
scenarios, these features are most probably miniature versions of hot
loops rooted at magnetic concentrations at opposite sides of a granule
in small emerging magnetic loops (or flux tubes).
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Title: Dynamics of polar plumes observed during the total solar
eclipse of August 1, 2008
Authors: Bělík, M.; Rušin, V.; Saniga, M.; Barczynski, K.
2012CoSka..42..125B Altcode:
We study dynamics of polar plumes observed during the 2008 eclipse
from three ground-based sites and the Hinode satellite. The speed
of apparent upward propagation, as inferred from the changes of
brightness within each plume, is found to lie in the range from 30
to 100 km s<SUP>-1</SUP>. Some white-light plumes located in polar
coronal holes were identified with their X-ray counterparts observed
by the Hinode satellite, which showed almost the same speed.
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Title: Polar plumes dynamics observed during total solar eclipses
Authors: Barczynski, K.; Bělík, M.; Marková, E.
2010nspm.conf..134B Altcode:
Following the successful observation of significant activity in the
polar plume during the total solar eclipse in 2006, the analysis of
the Sun's polar regions was also carried out in the images obtained in
multi-station observations of the eclipse of 2008. In this work polar
plumes showing similar although much less significant manifestation
of the dynamics have been identified. The dynamics evolution rates
have been obtained from comparing the pictures taken at different
times. The results are compared with the corresponding phenomena
observed in X-rays from the HINODE satellite.
