Amplitude equations for nonadiabatic nonradial pulsators.
Abstract
The amplitude equation formalism is extended to nonradial stellar pulsators. The resultant amplitude equations describe mode excitation and coupling, and they govern the nonlinear behavior of the amplitudes of the dominant modes. The amplitudes can be directly related to the intensities of the Fourier spectrum of the observed lightcurves. Nonadiabatic effects are fully incorporated in our formalism. The formalism applies, in principle, to any amount of stellar rotation and magnetic fields. In this paper explicit expressions are given for the nonlinear coupling coefficients up to third order for nonrotating, nonmagnetic stars. The inclusion of slow rotation is investigated in a companion paper.
 Publication:

Astronomy and Astrophysics
 Pub Date:
 November 1994
 Bibcode:
 1994A&A...291..481G
 Keywords:

 Formalism;
 Light Curve;
 Magnetic Stars;
 Nonadiabatic Theory;
 Nonlinear Systems;
 Pulse Amplitude;
 Stellar Oscillations;
 Stellar Rotation;
 White Dwarf Stars;
 Fourier Analysis;
 Mathematical Models;
 Stellar Magnetic Fields;
 Astrophysics;
 STARS: OSCILLATIONS;
 STARS: {DELTA} SCT;
 STARS: WHITE DWARF;
 SUN: OSCILLATIONS