Hot Subdwarf Stars

被引：390
作者：
Heber, Ulrich [1 ]
机构：
[1] Univ Erlangen Nurnberg, Dr Remeis Sternwarte Astron Inst, D-96049 Bamberg, Germany
来源：
ANNUAL REVIEW OF ASTRONOMY AND ASTROPHYSICS, VOL 47 | 2009年 / 47卷
关键词：
stars; atmospheres; binaries; evolution; pulsations; globular clusters; galaxies; early-type; HORIZONTAL-BRANCH STARS; ECLIPSING BINARY-SYSTEM; SPECTROSCOPIC TELESCOPE CAMPAIGN; BLANKETED MODEL ATMOSPHERES; IA PROGENITOR SURVEY; SUBLUMINOUS O-STARS; HELIUM WHITE-DWARF; NON-LTE ANALYSIS; B-STARS; SPECTRAL-ANALYSIS;
D O I：
10.1146/annurev-astro-082708-101836
中图分类号：
P1 [天文学];
学科分类号：
0704 ;
摘要：
Hot subdwarf stars (sdBs, sdOs) are core helium-burning stars at the blue end of the horizontal branch or have evolved even beyond that stage. They are found in all Galactic stellar populations and are sufficiently common to account for the UV-upturn of early-type galaxies. About half of the sdBs reside in close binaries; companions are white dwarfs or low-mass main-sequence stars. Binary population-synthesis models explain naturally the actual sdB binary fractions of field and globular cluster stars as well as of He-sdOs if white-dwarf mergers are considered. Hot helium flashes explain the chemical composition of He-sdOs. Asteroseismology of a dozen pulsating sdB stars allowed determination of their masses and detection of a planet to V391 Peg. The discoveries of an sdO star unbound to the Galaxy, potential SN Ia progenitors and probably a hidden population of neutron stars or black hole companions have great impact on astrophysics at large.
引用
收藏
页码：211 / 251
页数：41
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