Astronomy and Astrophysics – Astrophysics
Scientific paper
2004-12-20
Mon.Not.Roy.Astron.Soc. 363 (2005) 40-48
Astronomy and Astrophysics
Astrophysics
13 pages, 8 figures, accepted for publication in MNRAS
Scientific paper
10.1111/j.1365-2966.2005.09382.x
We present an analysis and interpretation of oscillation spectra for all 69 SX Phoenicis stars discovered in the field of the cluster. For most of the stars we have reliable absolute magnitudes and colors. Except of one, or perhaps two, objects, the stars are cluster members. Their pulsational behaviour is very diversified. Multiperiodic variability with at least part of the excited modes being nonradial is most common but there are also many cases of high amplitude, presumably radial mode, pulsators. In a number of such cases we have evidence for two radial modes being excited. Parameters of radial mode pulsators are in most cases consistent with standard evolutionary models for stars in the mass range 0.9-1.15 Mo. However, in four cases we have evidence that the masses are significantly lower than expected. Three objects show frequency triplets that may be interpreted in terms of rotational frequency splitting of l=1 modes. Implied equatorial velocities of rotation are from 10 to over 100 km/s. Nearly all measured frequencies fall in the ranges predicted for unstable modes. Two cases of low frequency variability are interpreted as being caused by tidal distortion induced by close companions.
Dziembowski Wojciech A.
Kaluzny Janusz
Olech Arkadiusz
Pamyatnykh Alexey A.
Pych Wojtek
No associations
LandOfFree
Cluster AgeS Experiment (CASE): SX Phe stars from the globular cluster Omega Centauri does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Cluster AgeS Experiment (CASE): SX Phe stars from the globular cluster Omega Centauri, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Cluster AgeS Experiment (CASE): SX Phe stars from the globular cluster Omega Centauri will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-576591