Period Changes in ω Centauri RR Lyrae Stars
Open Access
- 1 February 2001
- journal article
- research article
- Published by American Astronomical Society in The Astronomical Journal
- Vol. 121 (2) , 951-973
- https://doi.org/10.1086/318746
Abstract
A century of observations of ω Centauri allows us to accurately follow the period changes of a large sample of variable stars. Although the period changes are composed of monotone and irregular changes, period increases dominate in most of the RRab stars. The typical period increase rates are of the same order of magnitude as model calculations predict for the evolved, redward phase of horizontal-branch evolution. For the 44 well-observed RRab stars that show monotonic period changes, a mean rate of 0.15 days Myr-1 has been found. The period changes of the first-overtone RRc-type stars show a much more complex, irregular behavior.Keywords
All Related Versions
This publication has 20 references indexed in Scilit:
- The Globular Cluster ω Centauri and the Oosterhoff DichotomyThe Astronomical Journal, 2000
- The [Fe/H] dependence of the physical parameters of RRab stars – a semi-empirical approachNew Astronomy Reviews, 1999
- Spatial Metallicity Asymmetry in ω CentauriThe Astrophysical Journal, 1998
- The optical gravitational lensing experiment. Variable stars in globular clustersAstronomy and Astrophysics Supplement Series, 1997
- STELLAR PULSATIONS ACROSS THE HR DIAGRAM: Part IIAnnual Review of Astronomy and Astrophysics, 1996
- Oxygen-enhanced models for globular cluster stars. III - Horizontal-branch sequencesThe Astrophysical Journal Supplement Series, 1992
- AutotransfusionBMJ, 1967
- BOOKS REVIEWSThe British Journal of Aesthetics, 1965
- Changes in the period of RRab variables in omega Centauri.The Astronomical Journal, 1964
- Man and Dolphin. John C. Lilly. Doubleday, Garden City, N.Y., 1961. 312 pp. Illus. $4.95Science, 1961