J 2023

Analysis of photometric and spectroscopic variability of red supergiant Betelgeuse

JADLOVSKÝ, Daniel, Jiří KRTIČKA, Ernst PAUNZEN and Vladimír ŠTEFL

Basic information

Original name

Analysis of photometric and spectroscopic variability of red supergiant Betelgeuse

Authors

JADLOVSKÝ, Daniel (203 Czech Republic, guarantor, belonging to the institution), Jiří KRTIČKA (203 Czech Republic, belonging to the institution), Ernst PAUNZEN (40 Austria, belonging to the institution) and Vladimír ŠTEFL (203 Czech Republic, belonging to the institution)

Edition

New Astronomy, Amsterdam, Elsevier Science, 2023, 1384-1076

Other information

Language

English

Type of outcome

Článek v odborném periodiku

Field of Study

10308 Astronomy

Country of publisher

Netherlands

Confidentiality degree

není předmětem státního či obchodního tajemství

References:

Impact factor

Impact factor: 2.000 in 2022

RIV identification code

RIV/00216224:14310/23:00130070

Organization unit

Faculty of Science

UT WoS

000892224100003

Keywords in English

Betelgeuse; Red supergiants; Radial velocity; Photometry; Spectroscopy; Stellar pulsations

Tags

Tags

International impact, Reviewed
Změněno: 31/1/2023 16:07, Mgr. Marie Šípková, DiS.

Abstract

V originále

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.