Shell helium-burning hot subdwarf B stars as candidates for blue large-amplitude pulsators

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F67985815%3A_____%2F22%3A00604502" target="_blank" >RIV/67985815:_____/22:00604502 - isvavai.cz</a>

Result on the web

<a href="https://hdl.handle.net/11104/0361929" target="_blank" >https://hdl.handle.net/11104/0361929</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1051/0004-6361/202244571" target="_blank" >10.1051/0004-6361/202244571</a>

Result language

angličtina

Original language name

Shell helium-burning hot subdwarf B stars as candidates for blue large-amplitude pulsators

Original language description

Blue large-amplitude pulsators (BLAPs) are a newly discovered type of variable star. Their typical pulsation periods are on the order of a few tens of minutes, with relatively large amplitudes of 0.2-0.4 mag in optical bands, and their rates of period changes are on the order of 10(-7) yr(-1) (both positive and negative). They are extremely rare objects and attempts to explain their origins and internal structures have attracted a great deal of attention. Previous studies have proposed that BLAPs may be pre-white dwarfs, with masses around 0.3 M circle dot, or core-helium-burning stars in the range of similar to 0.7-1.1 M circle dot. In this work, we use a number of MESA models to compute and explore whether BLAPs could be explained as shell helium-burning subdwarfs type B (SHeB sdBs). The models that best match existing observational constraints have helium core masses in the range of similar to 0.45-0.5 M circle dot. Our model predicts that the positive rate of period change may evolve to negative. The formation channels for SHeB sdBs involve binary evolution and although the vast majority of BLAPs do not appear to be binaries (with the exception of HD 133729), the observational constraints are still very poor. Motivated by these findings, we explored the Roche lobe overflow channel. Of the 304 binary evolution models we computed, about half of them are able to produce SHeB sdBs in long-period binaries that evade detection from the limited observations that are currently available.

Czech name

—

Czech description

—

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

<a href="/en/project/GA22-34467S" target="_blank" >GA22-34467S: Binary interaction on the red giant branch: Hot subdwarfs as a test case.</a><br>

Continuities

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Publication year

2022

Confidentiality

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

Name of the periodical

Astronomy & Astrophysics

ISSN

0004-6361

e-ISSN

1432-0746

Volume of the periodical

668

Issue of the periodical within the volume

Dec.

Country of publishing house

FR - FRANCE

Number of pages

22

Pages from-to

A112

UT code for WoS article

000931907600008

EID of the result in the Scopus database

2-s2.0-85145442140