Catalog of Galactic β Cephei stars

Author(s)
Anamarija Stankov, Gerald Handler
Abstract

We present an extensive and up-to-date catalog of Galactic ? Cephei stars. This catalog is intended to give a comprehensive overview of observational characteristics of all known ? Cephei stars, covering information until 2004 June. Ninety-three stars could be confirmed to be ? Cephei stars. We use data from more than 250 papers published over the last nearly 100 years, and we provide over 45 notes on individual stars. For some stars we reanalyzed published data or conducted our own analyses. Sixty-one stars were rejected from the final ? Cephei list, and 77 stars are suspected to be ? Cephei stars. A list of critically selected pulsation frequencies for confirmed ? Cephei stars is also presented.

 

We analyze the ? Cephei stars as a group, such as the distributions of their spectral types, projected rotational velocities, radial velocities, pulsation periods, and Galactic coordinates. We confirm that the majority of the ? Cephei stars are multiperiodic pulsators. We show that, besides two exceptions, the ? Cephei stars with high pulsation amplitudes are slow rotators. Those higher amplitude stars have angular rotational velocities in the same range as the high-amplitude ? Scuti stars (Prot>~3 days).

 

We construct a theoretical HR diagram that suggests that almost all 93 ? Cephei stars are main-sequence objects. We discuss the observational boundaries of ? Cephei pulsation and the physical parameters of the stars. We corroborate that the excited pulsation modes are near to the radial fundamental mode in frequency and we show that the mass distribution of the stars peaks at 12 Msolar. We point out that the theoretical instability strip of the ? Cephei stars is filled neither at the cool nor at the hot end and attempt to explain this observation.

Organisation(s)
Department of Astrophysics
External organisation(s)
Science and Operations Department - Science Division (SCI-SC)
Journal
The Astrophysical Journal Supplement Series
Volume
158
Pages
193-216
No. of pages
24
ISSN
0067-0049
DOI
https://doi.org/10.1086/429408
Publication date
2005
Peer reviewed
Yes
Austrian Fields of Science 2012
1030 Physics, Astronomy, 103003 Astronomy
Portal url
https://ucrisportal.univie.ac.at/en/publications/ede8b199-066a-42f2-b184-a4c448df9780