A new class of rapidly pulsating star .3. Oscillations in EC 10228-0905 and pulsation analysis

被引:63
作者
Stobie, RS
Kawaler, SD
Kilkenny, D
ODonoghue, D
Koen, C
机构
[1] IOWA STATE UNIV,DEPT PHYS & ASTRON,AMES,IA 50211
[2] UNIV CAPE TOWN,DEPT ASTRON,ZA-7700 RONDEBOSCH,SOUTH AFRICA
关键词
surveys; binaries; general; stars; individual; EC; 10228-0905; oscillations; subdwarfs; variables; other;
D O I
10.1093/mnras/285.3.651
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
EC 10228-0905 is the third pulsating sdB+ star to be announced. High-speed photometry reveals three periods present in the range P=139-152 s with semiamplitudes of less than 10 mmag. All periods show evidence of variable amplitude. Pulsation models have been calculated for sdB stars with log g similar to 6.0 and T(eff)similar to 35 000 K. These all have radial and non-radial modes with periods in the observed range. No unique mode identification is possible at present, but it is clear that at least some of the modes are non-radial. No stars have been predicted to pulsate in this region of the Hertzsprung-Russell (HR) diagram and the cause of the pulsation is not yet understood.
引用
收藏
页码:651 / 656
页数:6
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