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arXiv · astro-ph/0309708

Instabilities of captured shocks in the envelopes of massive stars

M. Grott·W. Glatzel·S. Chernigovski
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Abstract

The evolution of strange mode instabilities into the non linear regime has been followed by numerical simulation for an envelope model of a massive star having solar chemical composition, M=50M_sun, T_eff=10^4K and L=1.17*10^6 L_sun. Contrary to previously studied models, for these parameters shocks are captured in the H-ionisation zone and perform rapid oscillations within the latter. A linear stability analysis is performed to verify that this behaviour is physical. The origin of an instability discovered in this way is identified by construction of an analytical model. As a result, the stratification turns out to be essential for instability. The difference to common stratification instabilities, e.g., convective instabilities, is discussed.

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M. Grott, W. Glatzel, S. Chernigovski. 2003-09-25. Instabilities of captured shocks in the envelopes of massive stars. https://doi.org/10.1111/j.1365-2966.2004.07222.x

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