Frequency ratio method for seismic modeling of γ Doradus stars
Abstract
A method for obtaining asteroseismological information of a γ Doradus oscillating star showing at least three pulsation frequencies is presented. This method is based on a first-order asymptotic g-mode expression, in agreement with the internal structure of γ Doradus stars. The information obtained is twofold: 1) a possible identification of the radial order n and degree ℓ of observed frequencies (assuming that these have the same ℓ), and 2) an estimate of the integral of the buoyancy frequency (Brunt-Väisälä) weighted over the stellar radius along the radiative zone. The accuracy of the method as well as its theoretical consistency are also discussed for a typical γ Doradus stellar model. Finally, the frequency ratios method has been tested with observed frequencies of the γ Doradus star HD 12901. The number of representative models verifying the complete set of constraints (the location in the HR diagram, the Brunt-Väisälä frequency integral, the observed metallicity and frequencies and a reliable identification of n and ℓ) is drastically reduced to six.
- Publication:
-
Astronomy and Astrophysics
- Pub Date:
- March 2005
- DOI:
- 10.1051/0004-6361:20041752
- arXiv:
- arXiv:astro-ph/0411183
- Bibcode:
- 2005A&A...432..189M
- Keywords:
-
- stars: oscillations;
- stars: interiors;
- stars: evolution;
- stars: individual: HD 12901;
- Astrophysics
- E-Print:
- 11 pages, 12 figures