J/A+A/671/A130 CLV curves of 10 spectral lines taken with SST (Pietrow+, 2023)
Center-to-limb variation of spectral lines and continua observed with
SST/CRISP and SST/CHROMIS.
Pietrow A.G.M., Kiselman D., Adriienko O., Petit dit de la Roche D.J.M.,
Diaz Baso, C. J., Calvo F.
<Astron. Astrophys. 671, A130 (2023)>
=2023A&A...671A.130P 2023A&A...671A.130P (SIMBAD/NED BibCode)
ADC_Keywords: Sun ; Spectroscopy
Keywords: methods: observational - line: formation - Sun: photosphere -
Sun: atmosphere - Sun - chromosphere
Abstract:
Observations of center-to-limb variations (CLV) of spectral lines and
continua provide a good test for the accuracy of models of solar and
stellar atmospheric structure and spectral-line formation. They are
also widely used to constrain elemental abundances and are becoming
increasingly important in atmospheric studies of exoplanets. However,
only a few such data sets exist for chromospheric lines. We aim to
create a set of standard profiles by means of mosaics made with the
CRISP and CHROMIS instruments of the Swedish 1-m Solar Telescope
(SST), as well as to explore the robustness of said profiles obtained
using this method. For each spectral line we use a mosaic that ranges
from the center to the limb. Each of these mosaics are averaged down
to 50 individual spectral profiles, spaced by 0.02 in the µ scale.
These profiles are corrected for p-mode oscillations, and their line
parameters (equivalent width, line shift, full-width at half-maximum,
and line depth) are then compared against literature values where
possible. We present a set of 50 average profiles that are spaced
equidistantly along the cosine of the heliocentric angle (µ) by
steps of 0.02 for five continuum points between 4001 and 7772Å, as
well as ten of the most commonly observed spectral lines at the SST
(CaII H & K, Hβ, MgI 5173Å, CI 5380Å, FeI 6173Å, FeI
6301Å, Hα, OI 7772Å, and CaII 8542Å). Center-to-limb
variation of line profiles and continua are shared in the CDS as
machine-readable tables, providing a quantitative constraint on
theoretical models that aim to model stellar atmospheres.
Description:
Limbdarkening curves of 10 spectral lines and continua commonly
observed with the SST. Each set consists of 50 average profiles that
are spaced equidistantly along the cosine of the heliocentric angle
(µ) by steps of 0.02. The following lines are included
The following lines are included
Ca II H
Ca II K
Hβ
Fe I 5172Å
Mg I 5173Å
Ti I 5174Å
Fe I 5379Å
C I 5380Å
Ti II 5381Å
Fe I 6173Å
Fe I 6301Å
Hα
O I 7772Å
Ca II 8542Å
For each the wavelength, mu positions, intensity, smoothened
intensity, variance, and number of averaged pixels are given.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
cont7771.dat 99 50 Continuum values of the 7771 angstrom continuum
list.dat 95 15 List of fits files of limb-darkening curves and
continua commonly observed with the SST
fits/* . 15 *Individual fits files
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Note on fits/*: files *cont.fits with 4 extensions:
MU (mu-angle), INT (Intensity), INT_VAR (std per mu angle) and
INT_CONT (number of averaged pixels)
files *clv.fits with 7 extensions:
WAV (wavelength), MU (mu-angle), INT (Intensity),
INT_SMOOTH (smoothened intensity), INT_VAR (variance),
INT_COUNT (number of averaged pixels) and SSTINSTRUMENTPSF (PSF instrument)
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Byte-by-byte Description of file: cont7771.dat
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Bytes Format Units Label Explanations
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1- 24 E24.19 --- Int Intensity
26- 49 E24.19 --- mu mu angle (cosine of the heliocentric angle)
51- 74 E24.19 --- Int-var std per mu angle
76- 99 E24.19 --- Int-cont amount of pixels that was averaged over
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Byte-by-byte Description of file: list.dat
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Bytes Format Units Label Explanations
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1- 14 A14 --- FileName Name of the fits file in subdirectory fits
16- 95 A80 --- Title Title of the file
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Acknowledgements:
Alexander Pietrow, apietrow(at)aip.de
(End) Patricia Vannier [CDS] 08-Dec-2022