Spherically symmetric model atmospheres using approximate lambda operators V. Static inhomogeneous atmospheres of hot dwarf stars

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F67985815%3A_____%2F21%3A00552605" target="_blank" >RIV/67985815:_____/21:00552605 - isvavai.cz</a>

Výsledek na webu

<a href="https://doi.org/10.1051/0004-6361/202039707" target="_blank" >https://doi.org/10.1051/0004-6361/202039707</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1051/0004-6361/202039707" target="_blank" >10.1051/0004-6361/202039707</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Spherically symmetric model atmospheres using approximate lambda operators V. Static inhomogeneous atmospheres of hot dwarf stars

Popis výsledku v původním jazyce

We aim to investigate the effects of clumping on atmospheric structure for the special case of a static, spherically symmetric atmosphere assuming microclumping and a 1D geometry. Static, spherically symmetric, non-LTE (local thermodynamic equilibrium) model atmospheres were calculated using the recent version of our code, which includes optically thin clumping. The matter is assumed to consist of dense clumps and a void interclump medium. Clumping is considered by means of clumping and volume filling factors, assuming all clumps are optically thin. Enhanced opacity and emissivity in clumps are multiplied by a volume filling factor to obtain their mean values. These mean values are used in the radiative transfer equation. Equations of kinetic equilibrium and the thermal balance equation use clump values of densities. Equations of hydrostatic and radiative equilibrium use mean values of densities. The atmospheric structure was calculated for selected stellar parameters. Moderate differences were found in temperature structure. However, clumping causes enhanced continuum radiation for the Lyman-line spectral region, while radiation in other parts of the spectrum is lower, depending on the adopted model. The atomic level departure coefficients are influenced by clumping as well.

Název v anglickém jazyce

Spherically symmetric model atmospheres using approximate lambda operators V. Static inhomogeneous atmospheres of hot dwarf stars

Popis výsledku anglicky

We aim to investigate the effects of clumping on atmospheric structure for the special case of a static, spherically symmetric atmosphere assuming microclumping and a 1D geometry. Static, spherically symmetric, non-LTE (local thermodynamic equilibrium) model atmospheres were calculated using the recent version of our code, which includes optically thin clumping. The matter is assumed to consist of dense clumps and a void interclump medium. Clumping is considered by means of clumping and volume filling factors, assuming all clumps are optically thin. Enhanced opacity and emissivity in clumps are multiplied by a volume filling factor to obtain their mean values. These mean values are used in the radiative transfer equation. Equations of kinetic equilibrium and the thermal balance equation use clump values of densities. Equations of hydrostatic and radiative equilibrium use mean values of densities. The atmospheric structure was calculated for selected stellar parameters. Moderate differences were found in temperature structure. However, clumping causes enhanced continuum radiation for the Lyman-line spectral region, while radiation in other parts of the spectrum is lower, depending on the adopted model. The atomic level departure coefficients are influenced by clumping as well.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10308 - Astronomy (including astrophysics,space science)

Projekt

<a href="/cs/project/GA18-05665S" target="_blank" >GA18-05665S: Ztráta hmoty v pozdních fázích vývoje hmotných hvězd</a><br>

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2021

Kód důvěrnosti údajů

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

Název periodika

Astronomy & Astrophysics

ISSN

0004-6361

e-ISSN

1432-0746

Svazek periodika

655

Číslo periodika v rámci svazku

November

Stát vydavatele periodika

FR - Francouzská republika

Počet stran výsledku

16

Strana od-do

A35

Kód UT WoS článku

000716102400003

EID výsledku v databázi Scopus

2-s2.0-85119092197