Progress on the Front of Pulsating Subdwarf B Stars
- Cite this article as:
- Fontaine, G., Green, E.M., Brassard, P. et al. Astrophys Space Sci (2004) 291: 379. doi:10.1023/B:ASTR.0000044348.61224.de
We briefly review the recent advances that have been made on the front of pulsating subdwarf B (sdB) stars. The first family of sdB pulsators, the EC 14026 stars, was discovered a few years ago and consists of short-period (∼100−200 s) p-mode variables. The second type of pulsating sdB’s consists of the PG 1716+426 stars, a group of variables showing long-period (∼1 h) g-mode pulsations. The existence of the latter was first reported less than a year ago. While the two types of sdB pulsators differ markedly in their observational characteristics, we recently found a unifying property in the sense that the observed modes in these objects are excited through the same driving process, a classic kappa mechanism associated with the radiative levitation of iron in the stellar envelope.