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arXiv · 1802.01495

Instability, finite amplitude pulsation and mass-loss in models of massive OB-type stars

Abhay Pratap Yadav·Wolfgang Glatzel
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Abstract

Variability and mass-loss are common phenomena in massive OB-type stars. It is argued that they are caused by violent strange mode instabilities identified in corresponding stellar models. We present a systematic linear stability analysis with respect to radial perturbations of massive OB-type stars with solar chemical composition and masses between 23 to 100 M$_{\odot}$. For selected unstable stellar models, we perform non-linear simulations of the evolution of the instabilities into the non-linear regime. Finite amplitude pulsations with periods in the range between hours and 100 days are found to be the final result of the instabilities. The pulsations are associated with a mean acoustic luminosity which can be the origin of a pulsationally driven wind. Corresponding mass-loss rates lie in the range between 10$^{-9}$ and 10$^{-4}$ M$_{\odot}$ yr$^{-1}$ and may thus affect the evolution of massive stars.

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Abhay Pratap Yadav, Wolfgang Glatzel. 2018-02-05. Instability, finite amplitude pulsation and mass-loss in models of massive OB-type stars. https://doi.org/10.1093/mnras/stx1808

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