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arXiv · 0709.4606

A photometric study of Be stars located in the seismology fields of COROT

J. Gutierrez-Soto·J. Fabregat·J. Suso·M. Lanzara·R. Garrido·A-M. Hubert·M. Floquet
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Abstract

Context: In preparation for the COROT mission, an exhaustive photometric study of Be stars located in the seismology fields of the COROT mission has been performed. The very precise and long-time-spanned photometric observations gathered by the COROT satellite will give important clues of the origin of the Be phenomenon. Aims: The aim of this work is to find short-period variable Be stars located in the seismology fields of COROT and to study and characterise their pulsational properties. Methods: Light curves obtained at the Observatorio de Sierra Nevada together with data from Hipparcos and ASAS-3 of a total of 84 Be stars have been analysed in order to search for short-term variations. We have applied standard Fourier techniques and non-linear least-square fitting to the time series. Results: We have found 7 multiperiodic, 21 mono-periodic and 26 non-variable Be stars. Short-term variability has been detected in 74% of early-type Be stars and in 31% of mid- to late-type Be stars. We have shown that non-radial pulsations are most frequent among Be stars than in slow-rotating B stars of the same spectral range.

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J. Gutierrez-Soto, J. Fabregat, J. Suso, M. Lanzara, R. Garrido, A-M. Hubert, M. Floquet. 2007-09-28. A photometric study of Be stars located in the seismology fields of COROT. https://doi.org/10.1051/0004-6361:20078252

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