Asteroseismology of hot subdwarf B stars observed with TESS: discovery of two new gravity mode pulsating stars

被引：0

作者：

Uzundag M. ^{[1
,2
]}

Silvotti R. ^{[3
]}

Baran A.S. ^{[4
,5
]}

Vučković M. ^{[1
]}

Németh P. ^{[6
]}

Sahoo S.K. ^{[4
,7
]}

Reed M. ^{[8
]}

机构：

[1] Instituto de Física y Astronomía, Universidad de Valparaíso, Gran Bretaña 1111, Playa Ancha, Valparaíso

[2] European Southern Observatory, Alonso de Cordova, Santiago

[3] INAF-Osservatorio Astrofisico di Torino, strada dell’Osservatorio 20, Pino Torinese

[4] Astronomical Observatory, University of Warsaw, Al. Ujazdowskie 4, Warszawa

[5] Astroserver.org, Fő tér 1, Malomsok

[6] Nicolaus Copernicus Astronomical Centre, Polish Academy of Sciences, ul. Bartycka 18, Warsaw

[7] Department of Physics, Astronomy and Materials Science, Missouri State University, 901 S. National, Springfield, 65897, MO

来源：

Bulletin de la Societe Royale des Sciences de Liege | 2023年 / 92卷 / 02期

关键词：

asteroseismology; stars: evolution; stars: horizontal-branch; Stars:; individual:; TIC; 033834484; 309658435; stars: interiors; stars: oscillations (including pulsations); stars: subdwarfs;

D O I：

10.255118/0037-9565.11294

中图分类号：

学科分类号：

摘要：

TIC 033834484 and TIC 309658435 are long-period pulsating subdwarf B stars, which were observed extensively (675 and 621 days, respectively) by the Transiting Exoplanet Survey Satellite (TESS). The high-precision photometric light curve reveals the presence of more than 40 pulsation modes including both stars. All the oscillation frequencies that we found are associated with gravity (g)-mode pulsations, with frequencies spanning from ∼80 µHz (2 500 s) to ∼400 µHz (12 000 s). We utilize the asteroseismic tools including asymptotic period spacings and rotational frequency multiplets in order to identify the pulsational modes. We found dipole (l = 1) mode sequences for both targets and calculate the mean period spacing of dipole modes (∆Pl=1), which allows us to identify the modes. Frequency multiplets provide a rotation period of ∼64 d for TIC 033834484. From follow-up ground-based spectroscopy, we find that TIC 033834484 has an effective temperature of 24 210 K (140), a surface gravity of log g/cms−2 = 5.28 (03) and TIC 309658435 has an effective temperature of 25 910 K (150), a surface gravity of log g/cms−2 = 5.48 (03). © 2023 Societe Royale des Sciences de Liege. All rights reserved.

引用

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