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arXiv · astro-ph/0110076

Nonlinear Beat Cepheid and RR Lyrae Models

Z. Kollath·J. R. Buchler·R. Szabo·Z. Csubry
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Abstract

The numerical hydrodynamic modelling of beat Cepheid behavior has been a long standing quest in which purely radiative models had failed consistently. We find that beat pulsations occur naturally when {\it turbulent convection} is accounted for in our hydrodynamics code. The development of a relaxation code and of a Floquet stability analysis greatly facilitates the search for and the analysis of beat Cepheid models. The conditions for the occurrence of beat behavior can be understood easily and at a fundamental level with the help of amplitude equations.

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Z. Kollath, J. R. Buchler, R. Szabo, Z. Csubry. 2001-10-03. Nonlinear Beat Cepheid and RR Lyrae Models. https://doi.org/10.1051/0004-6361%3A20020182

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