CoRoT observations of O stars: diverse origins of variability

R. Blomme; M. Briquet; P. Degroote; L. Mahy; C. Aerts; J. Cuypers; M. Godart; E. Gosset; M. Hareter; J. Montalban; T. Morel; M. F. Nieva; A. Noels; R. Oreiro; E. Poretti; N. Przybilla; M. Rainer; G. Rauw; F. Schiller; S. Simon-Diaz; K. Smolders; P. Ventura; M. Vuckovic; M. Auvergne; A. Baglin; F. Baudin; C. Catala; E. Michel; R. Samadi

arXiv · 1109.1999

CoRoT observations of O stars: diverse origins of variability

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Abstract

Six O-type stars were observed continuously by the CoRoT satellite during a 34.3-day run. The unprecedented quality of the data allows us to detect even low-amplitude stellar pulsations in some of these stars (HD 46202 and the binaries HD 46149 and Plaskett's star). These cover both opacity-driven modes and solar-like stochastic oscillations, both of importance to the asteroseismological modelling of O stars. Additional effects can be seen in the CoRoT light curves, such as binarity and rotational modulation. Some of the hottest O-type stars (HD 46223, HD 46150 and HD 46966) are dominated by the presence of red-noise: we speculate that this is related to a sub-surface convection zone.

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R. Blomme, M. Briquet, P. Degroote, L. Mahy, C. Aerts, J. Cuypers, M. Godart, E. Gosset, M. Hareter, J. Montalban, T. Morel, M. F. Nieva, A. Noels, R. Oreiro, E. Poretti, N. Przybilla, M. Rainer, G. Rauw, F. Schiller, S. Simon-Diaz, K. Smolders, P. Ventura, M. Vuckovic, M. Auvergne, A. Baglin, F. Baudin, C. Catala, E. Michel, R. Samadi. 2011-09-09. CoRoT observations of O stars: diverse origins of variability. https://arxiv.org/abs/1109.1999

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