Analysis of photometric and spectroscopic variability of red supergiant Betelgeuse

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216224%3A14310%2F23%3A00130070" target="_blank" >RIV/00216224:14310/23:00130070 - isvavai.cz</a>

Výsledek na webu

<a href="https://arxiv.org/pdf/2211.04380.pdf" target="_blank" >https://arxiv.org/pdf/2211.04380.pdf</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.newast.2022.101962" target="_blank" >10.1016/j.newast.2022.101962</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Analysis of photometric and spectroscopic variability of red supergiant Betelgeuse

Popis výsledku v původním jazyce

Betelgeuse is a pulsating red supergiant whose brightness is semi periodically variable and in February 2020 reached a historical minimum, the Great Dimming. The aims of this study are to characterize Betelgeuse’s variability based on available archival data and to study possible causes of light variability. Many spectra, from ultraviolet and optical regions, were evaluated for spectral analysis. The spectra were used primarily to determine radial velocities from different layers of atmosphere and their long-term evolution. Additionally, photometric data were analysed in different filters as well, to construct light curves and to determine periods of the variability. Spectroscopic and photometric variability are compared to each other and given into a context with the Great Dimming. The two most dominant photometric periods are P1=2190±270d and P2=417±17d, while the dominant optical (photospheric) radial velocity periods are P1,vr=2510±440d and P2,vr=415±11d. During the same time, the radial velocity determined from ultraviolet spectra also shows variability and is distinctively different from the variability of photospheric velocity, undergoing longer periods of variability. We attribute these velocities to the velocities at the base of outflowing wind. We also report a maximum of stellar wind velocity during the Great Dimming, accompanied by the previously reported minimum of brightness and the maximum of photospheric radial velocity. After the Dimming, Betelgeuse’s mode of variability has fundamentally changed and is now instead following a shorter period of ∼200d.

Název v anglickém jazyce

Analysis of photometric and spectroscopic variability of red supergiant Betelgeuse

Popis výsledku anglicky

Betelgeuse is a pulsating red supergiant whose brightness is semi periodically variable and in February 2020 reached a historical minimum, the Great Dimming. The aims of this study are to characterize Betelgeuse’s variability based on available archival data and to study possible causes of light variability. Many spectra, from ultraviolet and optical regions, were evaluated for spectral analysis. The spectra were used primarily to determine radial velocities from different layers of atmosphere and their long-term evolution. Additionally, photometric data were analysed in different filters as well, to construct light curves and to determine periods of the variability. Spectroscopic and photometric variability are compared to each other and given into a context with the Great Dimming. The two most dominant photometric periods are P1=2190±270d and P2=417±17d, while the dominant optical (photospheric) radial velocity periods are P1,vr=2510±440d and P2,vr=415±11d. During the same time, the radial velocity determined from ultraviolet spectra also shows variability and is distinctively different from the variability of photospheric velocity, undergoing longer periods of variability. We attribute these velocities to the velocities at the base of outflowing wind. We also report a maximum of stellar wind velocity during the Great Dimming, accompanied by the previously reported minimum of brightness and the maximum of photospheric radial velocity. After the Dimming, Betelgeuse’s mode of variability has fundamentally changed and is now instead following a shorter period of ∼200d.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10308 - Astronomy (including astrophysics,space science)

Projekt

—

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2023

Kód důvěrnosti údajů

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

Název periodika

New Astronomy

ISSN

1384-1076

e-ISSN

1384-1092

Svazek periodika

99

Číslo periodika v rámci svazku

February

Stát vydavatele periodika

NL - Nizozemsko

Počet stran výsledku

10

Strana od-do

1-10

Kód UT WoS článku

000892224100003

EID výsledku v databázi Scopus

2-s2.0-85141452875