On the spectacular variations of Be stars Evidence for a temporarily tilted circumstellar disk
نویسنده
چکیده
A new explanation for the spectacular emission line variations occuring in the Be stars γ Cas and 59 Cyg is presented. We propose a circumstellar Keplerian disk, tilted with respect to the equatorial plane. The precessing nodal and apsidal line causes a variation in the emission line widths and profile shapes. In particular the sequence of alternating shellphases and narrow single-peak phases is proposed to be due to an apparent variation in the disk inclination.
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