Letter to the Editor A nonlinear model for RR Lyrae double mode pulsation
نویسنده
چکیده
The Vienna nonlinear code for modelling pulsating stars is applied to the problem of RR Lyrae double mode pulsation. For stellar parameters of M = 0.65 M , log(L/L ) = 1.72 and XYZ=(0.760, 0.239, 0.001) we find a stable double mode solution in a small effective temperature range around 6820 K. The fundamental period is given by P0 = 0.5279 days and period and amplitude ratios corresponding to P1/P0 = 0.7468 and A1/A0 = 2.943 lie within the range of observed RR Lyrae double mode parameters.
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