A&A 399, 287-296 (2003)
DOI: 10.1051/0004-6361:20021776
Line profile variability in the spectra of Oef stars
I. BD + 60
2522
G. Rauw, M. De Becker and J.-M. Vreux Institut d'Astrophysique et de Géophysique, Université de Liège, Allée du 6 Août, Bât. B5c, 4000 Liège (Sart Tilman), Belgium
(Received 5 November 2002 / Accepted 14 November 2002)
Abstract
We report the analysis of a long term observing campaign designed to monitor the spectroscopic variability of the Oef star
BD
2522. We find that the double-peaked He II
4686 emission line undergoes strong profile variability on time scales of 2-3 day. However, the time scale as well as the
pattern of these variations turn out to be epoch dependent and the phenomenon is thus most likely not ruled by a single stable
clock. On the other hand, the absorption lines in the spectrum of BD
2522 display line profile variability on time scales of a few hours that might be related to non-radial pulsations. We tentatively
propose that the beating of several non-radial pulsation modes triggers transient large-scale density perturbations in a confined
stellar wind that produce the 2-3 day time scale variability.
Key words: line: profiles -- stars: early-type -- stars: mass-loss -- stars: individual: BD
Offprint request: G. Rauw, rauw@astro.ulg.ac.be
SIMBAD Objects
© ESO 2003

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