An extensive photometric study of the Blazhko RR Lyrae star MW Lyr: II. Changes in the physical parameters
arXiv:0811.3095 · doi:10.1111/j.1365-2966.2008.14261.x
Abstract
The analysis of the multicolour photometric observations of MW Lyr, a large modulation amplitude Blazhko variable, shows for the first time how the mean global physical parameters vary during the Blazhko cycle. About 1-2 percent changes in the mean radius, luminosity and surface effective temperature are detected. The mean radius and temperature changes are in good accordance with pulsation model results, which show that these parameters do indeed vary within this order of magnitude if the amplitude of the pulsation changes significantly. We interpret the phase modulation of the pulsation to be a consequence of period changes. Its magnitude corresponds exactly what one expects from the detected changes of the mean radius assuming that the pulsation constant remains the same during the modulation. Our results indicate that during the modulation the pulsation remains purely radial, and the underlying mechanism is most probably a periodic perturbation of the stellar luminosity with the modulation period.
10 figures, 2 tables. Accepted for publication in MNRAS
References in corpus (2)
Cited by in corpus (7)
- Kepler photometry of the prototypical Blazhko star RR Lyr: An old friend seen in a new light
- Revisiting CoRoT RR Lyrae stars: detection of period doubling and temporal variation of additional frequencies
- An In-Depth Spectroscopic Analysis of RR Lyr Variations over the Pulsation Cycle
- A cautionary tale of interpreting O-C diagrams: period instability in a classical RR Lyr Star Z CVn mimicking as a distant companion
- Automated Extended Aperture Photometry of K2 variable stars
- The first Baade-Wesselink analysis of Blazhko RR Lyrae stars: discrepancies between photometrically and spectroscopically determined radius variations
- Atmospheric dynamics and shock waves in RR Lyr -- I. The three H emissions