J/MNRAS/527/2940 Solar activity components intensity profiles (Cretignier+ 2024)
Stellar surface information from the Ca II H&K lines.
I. Intensity profiles of the solar activity components.
Cretignier M., Pietrow A.G.M, Aigrain S.
<Mon. Not. R. Astron. Soc. 527, 2940-2962 (2024)>
=2024MNRAS.527.2940C 2024MNRAS.527.2940C (SIMBAD/NED BibCode)
ADC_Keywords: Sun ; Spectroscopy
Keywords: line: profile - methods: data analysis - techniques: spectroscopic -
stars: activity - stars: chromospheres
Abstract:
The detection of Earth-like planets with the radial-velocity method is
currently limited by the presence of stellar activity signatures. On
rotational timescales, spots and plages (or faculae) are known to
introduce different RV signals, but their corrections require better
activity proxies. The best-known chromospheric activity proxies in the
visible are the CaII H & K lines, but the physical quantities
measured by their profiles need to be clarified. We first investigate
resolved images of the Sun in order to better understand the spectrum
of plages, spots, and the network using the Meudon spectroheliogram.
We show that distinct line profiles are produced by plages, spots, and
by the network component and we also derived the center-to-limb
variations of the three profiles. Some care is required to disentangle
their contributions due to their similarities. By combining
disk-integrated spectra from the ISS high-resolution spectrograph with
SDO direct images of the Sun, we managed to extract a high-resolution
emission spectrum of the different components, which tend to confirm
the spectra extracted from the Meudon spectroheliogram datacubes.
Similar results were obtained with the HARPS-N Sun-as-a-star spectra.
We concluded using a three-component model that the temporal variation
of the popular Sindex contains, on average for the 24th solar
cycle: 70±12% of plage, 26±12% of network and 4±4% of
spots. This preliminary investigation suggests that a detailed study
of the CaII H & K profiles may provide rich information about the
filling factor and distribution of different types of active regions.
Description:
CLV spectra for CaII H&K lines for spots, plage and quiet Sun
obtained with the Meudon spectroheliograms.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
quiet.dat 110 94 CLV profiles for quiet Sun
spot.dat 74 94 CLV profiles for spot Sun
plage.dat 74 94 CLV profiles for plage Sun
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Byte-by-byte Description of file: quiet.dat
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Bytes Format Units Label Explanations
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1- 2 I2 --- Index Index of the table
4- 11 F8.4 nm lambda Wavelength
13- 20 F8.6 % Flux0.078 Flux at mu=0.078
22- 30 F9.6 % Flux0.156 Flux at mu=0.156
32- 40 F9.6 % Flux0.253 Flux at mu=0.253
42- 50 F9.6 % Flux0.353 Flux at mu=0.353
52- 60 F9.6 % Flux0.452 Flux at mu=0.452
62- 70 F9.6 % Flux0.552 Flux at mu=0.552
72- 80 F9.6 % Flux0.646 Flux at mu=0.646
82- 90 F9.6 % Flux0.751 Flux at mu=0.751
92-100 F9.6 % Flux0.846 Flux at mu=0.846
102-110 F9.6 % Flux0.946 Flux at mu=0.946
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Byte-by-byte Description of file: spot.dat
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Bytes Format Units Label Explanations
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1- 2 I2 --- Index Index of the table
4- 11 F8.4 nm lambda Wavelength
13- 20 F8.6 --- Flux0.353 Flux ratio (AR/Quiet) at mu=0.353
22- 29 F8.6 --- Flux0.459 Flux ratio (AR/Quiet) at mu=0.459
31- 38 F8.6 --- Flux0.551 Flux ratio (AR/Quiet) at mu=0.551
40- 47 F8.6 --- Flux0.650 Flux ratio (AR/Quiet) at mu=0.650
49- 56 F8.6 --- Flux0.758 Flux ratio (AR/Quiet) at mu=0.758
58- 65 F8.6 --- Flux0.860 Flux ratio (AR/Quiet) at mu=0.860
67- 74 F8.6 --- Flux0.941 Flux ratio (AR/Quiet) at mu=0.941
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Byte-by-byte Description of file: plage.dat
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Bytes Format Units Label Explanations
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1- 2 I2 --- Index Index of the table
4- 11 F8.4 nm lambda Wavelength
13- 20 F8.6 --- Flux0.352 Flux ratio (AR/Quiet) at mu=0.352
22- 29 F8.6 --- Flux0.454 Flux ratio (AR/Quiet) at mu=0.454
31- 38 F8.6 --- Flux0.553 Flux ratio (AR/Quiet) at mu=0.553
40- 47 F8.6 --- Flux0.651 Flux ratio (AR/Quiet) at mu=0.651
49- 56 F8.6 --- Flux0.753 Flux ratio (AR/Quiet) at mu=0.753
58- 65 F8.6 --- Flux0.856 Flux ratio (AR/Quiet) at mu=0.856
67- 74 F8.6 --- Flux0.940 Flux ratio (AR/Quiet) at mu=0.940
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Acknowledgements:
Michael Cretignier, michael.cretignier(at)physics.ox.ac.uk
(End) Patricia Vannier [CDS] 24-Oct-2023