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arXiv · 1408.3485

Stability boundaries for massive stars in the sHR diagram

Hideyuki Saio·Cyril Georgy·Georges Meynet
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Abstract

Stability boundaries of radial pulsations in massive stars are compared with positions of variable and non-variable blue-supergiants in the spectroscopic HR (sHR) diagram (Langer & Kudritzki 2014), whose vertical axis is $4\log T_{\rm eff}-\log g \,(= \log L/M)$. Observational data indicate that variables tend to have higher $L/M$ than non-variables in agreement with the theoretical prediction. However, many variable blue-supergiants are found to have values of $L/M$ below the theoretical stability boundary; i.e., surface gravities seem to be too high by around 0.2-0.3 dex.

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Hideyuki Saio, Cyril Georgy, Georges Meynet. 2014-08-15. Stability boundaries for massive stars in the sHR diagram. https://doi.org/10.1017/s1743921314006838

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