Bibcode
Randall, S. K.; Calamida, A.; Fontaine, G.; Monelli, M.; Bono, G.; Alonso, M. L.; Van Grootel, V.; Brassard, P.; Chayer, P.; Catelan, M.; Littlefair, S.; Dhillon, V. S.; Marsh, T. R.
Referencia bibliográfica
The Messenger, vol. 164, p. 23-26
Advertised on:
6
2016
Número de citas
0
Número de citas referidas
0
Descripción
We recently discovered the first globular cluster hot subdwarf pulsators
in Omega Centauri (ω Cen). These stars were initially thought to
belong to the class of rapidly pulsating subdwarf B stars, which are
well established among the field star population and have become
showcases for asteroseismology. However, our spectroscopic analysis
revealed the ω Cen variables to be significantly hotter than
expected, indicating that they form a new class of subdwarf O pulsators
clustered around 50 000 K, not known among the field star population.
Non-adiabatic pulsation modelling suggests that the driver for the
pulsations occurs via the same iron opacity mechanism that is at work in
the rapidly pulsating subdwarf B stars.