A new class of rapidly pulsating star - III. Oscillations in EC 10228-0905 and pulsation analysis
Abstract
EC 10228-0905 is the third pulsating sdB+ star to be announced. High-speed photometry reveals three periods present in the range P=139-152s with semi-amplitudes of less than 10mmag. All periods show evidence of variable amplitude. Pulsation models have been calculated for sdB stars with log g~6.0 and T_eff~35 000K. 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.
- Publication:
-
Monthly Notices of the Royal Astronomical Society
- Pub Date:
- March 1997
- DOI:
- 10.1093/mnras/285.3.651
- Bibcode:
- 1997MNRAS.285..651S
- Keywords:
-
- SURVEYS;
- BINARIES: GENERAL;
- STARS: INDIVIDUAL: EC 10228-0905;
- STARS: OSCILLATIONS;
- SUBDWARFS;
- STARS: VARIABLES: OTHER