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

Juan Gutiérrez (1, 2, 3) , Juan Fabregat (1, 2, 3) , Julia Suso (4) , M. Lanzara (4) , Rafael Garrido (5) , Anne-Marie Hubert (2, 3) , Michèle Floquet (2, 3)

1 UV - Universitat de València
2 GEPI - Galaxies, Etoiles, Physique, Instrumentation
3 Physique stellaire et galactique
4 GACE-ICMUV, edificio Institutos de Investigación, polígono la Coma
5 IAA - Instituto de Astrofísica de Andalucía

Context: In preparation for the COROT mission, an exhaustive photometric study of Be stars located in the seismology fields of the mission has been performed. The very precise and long-time-spanned photometric observations gathered by the COROT satellite will give important clues on 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 for a total of 84 Be stars, were analysed in order to search for short-term variations. We applied standard Fourier techniques and non-linear least-square fitting to the time series.
Results: We found 7 multiperiodic, 21 mono-periodic and 26 non-variable Be stars. Short-term variability was detected in 74% of early-type Be stars and in 31% of mid- to late-type Be stars. We show that non-radial pulsations are more frequent among Be stars than in slow-rotating B stars of the same spectral range.

Domaines: Astrophysique [astro-ph]

Juan Gutiérrez, Juan Fabregat, Julia Suso, M. Lanzara, Rafael Garrido, et al.. A photometric study of Be stars located in the seismology fields of COROT. Astronomy and Astrophysics - A&A, 2007, 476, pp.927-933. ⟨10.1051/0004-6361:20078252⟩. ⟨hal-03785557⟩