Photometric amplitudes and phases of nonradial oscillation in rotating stars
- Author(s)
- J Daszynska-Daszkiewicz, Wojciech A. Dziembowski, Aleksiej Pamiatnych, Marie J. Goupil
- Abstract
Effects of rotational mode coupling on photometric parameters of stellar oscillations are studied. At moderate rotation rates, a strong coupling between modes of spherical harmonic degree, l, differing by 2 and of the same azimuthal order, m, takes place if the frequencies are close. This is a common situation amongst main sequence pulsators. Numerical results for a sequence of ß Cephei star models are reported for the two- and three-mode couplings. One consequence of mode coupling is that modes of higher degree should be considered in photometric mode identification. Modes with nominal degree l > 2 acquire substantial l = 2 components and therefore are more likely to reach detectable amplitudes. Coupled mode positions in the amplitude ratio - phase difference diagrams, based on multicolour photometry, become both aspect- and m-dependent. Examples of the mode path in the diagram with varying aspect are given. The diagrams remain a useful tool for mode identification in rotating stars but the tool must be used with care.
- Organisation(s)
- Department of Astrophysics
- External organisation(s)
- University of Wrocław, Nicolaus Copernicus University, Université de recherche Paris Sciences et Lettres
- Journal
- Astronomy & Astrophysics
- Volume
- 392
- Pages
- 151-159
- No. of pages
- 9
- ISSN
- 0004-6361
- Publication date
- 2002
- Peer reviewed
- Yes
- Austrian Fields of Science 2012
- 103003 Astronomy
- Portal url
- https://ucrisportal.univie.ac.at/en/publications/b19e70be-bc16-42b7-bdfc-bdee4ede97e2