Quiet-Sun hydrogen Lyman-alpha line profile derived from SOHO/SUMER solar-disk observations

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F67985815%3A_____%2F20%3A00537299" target="_blank" >RIV/67985815:_____/20:00537299 - isvavai.cz</a>

Result on the web

<a href="https://doi.org/10.1051/0004-6361/202039348" target="_blank" >https://doi.org/10.1051/0004-6361/202039348</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1051/0004-6361/202039348" target="_blank" >10.1051/0004-6361/202039348</a>

Result language

angličtina

Original language name

Quiet-Sun hydrogen Lyman-alpha line profile derived from SOHO/SUMER solar-disk observations

Original language description

We derive a reference quiet-Sun Lyman-alpha spectral profile that is representative of the Lyman-alpha radiation from the solar disk during a minimum of solar activity. This profile can serve as an incident radiation boundary condition for the radiative transfer modelling of chromospheric and coronal structures. Because the solar radiation in the Lyman lines is not constant over time but varies significantly with the solar cycle, we provide a method for the adaptation of the incident radiation Lyman line profiles (Lyman-alpha and higher lines) to a specific date. Moreover, we analyse how the change in the incident radiation influences the synthetic spectra produced by the radiative transfer modelling. We present the reference quiet-Sun Lyman-alpha profile and a table of coefficients describing the variation of the Lyman lines with the solar cycle throughout the lifetime of SOHO. The analysis of the influence of the change in the incident radiation shows that the synthetic spectra are strongly affected by the modification of the incident radiation boundary condition. The most pronounced impact is on the central and integrated intensities of the Lyman lines. There, the change in the synthetic spectra can often have the same amplitude as the change in the incident radiation itself. The impact on the specific intensities in the peaks of reversed Lyman-line profiles is smaller but still significant. The hydrogen H alpha line can also be considerably affected, despite the fact that the H alpha radiation from the solar disk does not vary with the solar cycle.

Czech name

—

Czech description

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Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

—

OECD FORD branch

10308 - Astronomy (including astrophysics,space science)

Project

Result was created during the realization of more than one project. More information in the Projects tab.

Continuities

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Publication year

2020

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Astronomy & Astrophysics

ISSN

1432-0746

e-ISSN

—

Volume of the periodical

644

Issue of the periodical within the volume

December

Country of publishing house

FR - FRANCE

Number of pages

16

Pages from-to

A109

UT code for WoS article

000598603000001

EID of the result in the Scopus database

2-s2.0-85097644328