Journal Article

An extensive photometric study of the Blazhko RR Lyrae star MW Lyr – II. Changes in the physical parameters*

J. Jurcsik, Á. Sódor, B. Szeidl, Z. Kolláth, H. A. Smith, Zs. Hurta, M. Váradi, A. Henden, I. Dékány, I. Nagy, K. Posztobányi, A. Szing, K. Vida and N. Vityi

in Monthly Notices of the Royal Astronomical Society

Published on behalf of The Royal Astronomical Society

Volume 393, issue 4, pages 1553-1562
Published in print March 2009 | ISSN: 0035-8711
Published online February 2009 | e-ISSN: 1365-2966 | DOI:
An extensive photometric study of the Blazhko RR Lyrae star MW Lyr – II. Changes in the physical parameters*

More Like This

Show all results sharing this subject:

  • Astronomy and Astrophysics


Show Summary Details


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 per cent 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.

Keywords: methods: data analysis; techniques: photometric; stars: horizontal branch; stars: individual: MW Lyr; stars: oscillations; stars: variables: other

Journal Article.  6072 words.  Illustrated.

Subjects: Astronomy and Astrophysics

Full text: subscription required

How to subscribe Recommend to my Librarian

Users without a subscription are not able to see the full content. Please, subscribe or login to access all content.