β Cep stars from a spectroscopic point of view

In this review we present the current status of line-profile-variation studies of β Cep stars. Such studies have been performed for 26 bright members of this class of pulsating stars in the past 25 years. We describe all these currently available data and summarize the interpretations based on them in terms of the excited pulsation modes. We emphasize that line-profile variations offer a much more detailed picture of the pulsational behaviour of pulsating stars compared to ground-based photometric data. The latter, however, remain necessary to unravel the often complex frequency pattern and to achieve unambiguous mode identification for multiperiodic β Cep stars and also to derive the pulsational properties of the faint members of the class. We highlight the statistical properties of the sample of 26 stars for which accurate spectroscopic studies are available and point out some future prospects. This revised version was published online in June 2006 with corrections to the Cover Date.     

Current status of asteroseismology

Asteroseismology, the extension of helioseismology to stars – solar-alike or not – has been an exciting and active field of research for about two decades. While over that period helioseismology has had great success in revealing the solar structure and its dynamics, progress in asteroseismology has been hampered by the observational challenge to carry out, primarily from the ground, high precision measurements on unresolved objects with a substantially lower flux.