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arXiv · astro-ph/0303046

Nonlinear Properties of the Semiregular Variable Stars

J. Robert Buchler·Zoltan Kollath
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Abstract

We demonstrate how, with a purely empirical analysis of the irregular lightcurve data, one can extract a great deal of information about the stellar pulsation mechanism. An application to R Sct thus shows that the irregular lightcurve is the result of the nonlinear interaction of two highly nonadiabatic pulsation modes, namely a linearly unstable, low frequency mode, and the second mode that, although linearly stable, gets entrained through a 2:1 resonance. In the parlance of nonlinear dynamics the pulsation is the result of a 4 dimensional chaotic dynamics.

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J. Robert Buchler, Zoltan Kollath. 2003-03-03. Nonlinear Properties of the Semiregular Variable Stars. https://doi.org/10.1007/978-94-010-0139-7_9

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