A survey of hot subdwarf pulsators in ω Cen

oleh: Catelan M., Monelli M., Alonso M.L., Green E.M., Fontaine G., Calamida A., Randal S.K., Bono G., Dhillon V.S., Marsh T.R.

Format: Article
Diterbitkan: EDP Sciences 2013-03-01

Deskripsi

We recently discovered an apparently new class of pulsating Extreme Horizontal Branch (EHB) star in ω Cen. Tightly clustered around ∼50,000 K, these H-rich sdO stars exhibit rapid, multi-periodic oscillations on a timescale of 100 s. While four such objects have been detected in ω Cen, no counterparts have yet been found among the field population. Conversely, the rapid sdB pulsators around 31,000 K that are well-studied in the Galactic field have yet to be found in a globular cluster. We discuss the implications of this and also report the discovery of a fifth EHB pulsator in ω Cen.