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Universal Scaling Laws for Solar and Stellar Atmospheric Heating: Catalog of Power-law Index between Solar Activity Proxies and Various Spectral IrradiancesThe formation of extremely hot outer atmospheres is one of the most prominent manifestations of magnetic activity common to late-type dwarf stars, including the Sun. It is widely believed that these atmospheric layers, the corona, transition region, and chromosphere, are heated by the dissipation of energy transported upwards from the stellar surface by the magnetic field. This is signified by the spectral line fluxes at various wavelengths, scaled with power-law relationships against the surface magnetic flux over a wide range of formation temperatures, which are universal to the Sun and Sunlike stars of different ages and activity levels. This study describes a catalog of power-law indices between solar activity proxies and various spectral line fluxes. Compared to previous studies, we expanded the number of proxies, which now includes the total magnetic flux, total sunspot number, total sunspot area, and the F10.7 cm radio flux, and further enhanced the number of spectral lines by a factor of 2. This provides the data to study in detail the flux–flux scaling laws from the regions specified by the temperatures of the corona (log(T/K) = 6–7) to those of the chromosphere (log(T/K) ∼ 4), as well as the reconstruction of various spectral line fluxes of the Sun in the past, F-, G-, and K-type dwarfs, and the modeled stars.
Document ID
20230002478
Acquisition Source
Goddard Space Flight Center
Document Type
Reprint (Version printed in journal)
Authors
Shin Toriumi ORCID
(Japan Aerospace Exploration Agency Tokyo, Japan)
Vladimir S. Airapetian ORCID
(American University Washington, DC)
Kosuke Namekata ORCID
(National Astronomical Observatory of Japan Mitaka-shi, Japan)
Yuta Notsu ORCID
(University of Colorado Boulder Boulder, Colorado, United States)
Date Acquired
February 22, 2023
Publication Date
September 30, 2022
Publication Information
Publication: Astrophysical Journal Supplement
Publisher: American Astronomical Society
Volume: 262
Issue: 2
Issue Publication Date: October 1, 2022
ISSN: 0067-0049
e-ISSN: 1538-4365
Subject Category
Astrophysics
Solar Physics
Funding Number(s)
CONTRACT_GRANT: 80GSFC23CA040
CONTRACT_GRANT: JSPS KAKENHI JP20KK0072
CONTRACT_GRANT: JSPS KAKENHI JP21H01124
CONTRACT_GRANT: JSPS KAKENHI JP21H04492
CONTRACT_GRANT: JSPS KAKENHI JP21J00316
CONTRACT_GRANT: JSPS KAKENHI JP21J00106
Distribution Limits
Public
Copyright
Portions of document may include copyright protected material.
Technical Review
Professional Review
Keywords
Stellar coronae
Stellar chromospheres
Solar spectral irradiance
Solar corona
Solar transition region
Solar chromosphere
Solar magnetic fields
Solar analogs
G dwarf stars
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