Pulsating B and Be stars in the Magellanic Clouds

P. D. Diago; J. Gutiérrez-Soto; J. Fabregat; C. Martayan; J. Suso

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arXiv · 0810.0166

Pulsating B and Be stars in the Magellanic Clouds

P. D. Diago·J. Gutiérrez-Soto·J. Fabregat·C. Martayan·J. Suso

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Abstract

Stellar pulsations in main-sequence B-type stars are driven by the $κ$-mechanism due to the Fe-group opacity bump. The current models do not predict the presence of instability strips in the B spectral domain at very low metallicities. As the metallicity of the Magellanic Clouds (MC) has been measured to be around $Z=0.002$ for the Small Magellanic Cloud (SMC) and $Z=0.007$ for the Large Magellanic Cloud (LMC), they constitute a very suitable objects to test these predictions. The aim of this work is to investigate the existence of B-type pulsators at low metallicities, searching for short-term periodic variability in a large sample of B and Be stars from the MC with accurately determined fundamental astrophysical parameters.

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P. D. Diago, J. Gutiérrez-Soto, J. Fabregat, C. Martayan, J. Suso. 2008-10-02. Pulsating B and Be stars in the Magellanic Clouds. https://arxiv.org/abs/0810.0166

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