In the past decade, a consensus has emerged regarding the nature of classical Be stars:
They are very rapidly rotating main sequence B stars, which, through a still unknown, but …

The interest in X/γ-ray Astronomy has grown enormously in the last decades thanks to the
ability to send X-ray space missions above the Earth's atmosphere. There are more than half …

Context. About 20% of all B-type stars are classical Be stars–stars whose spectra imply the
presence of a circumstellar decretion disk. The disk phenomenon is strongly correlated with …

Context. About 2/3 of the Be stars present the so-called variations, a phenomenon
characterized by the quasi-cyclic variation in the ratio between the violet and red emission …

The characterization of gas in the inner disks around young stars is of particular interest
because of its connection to planet formation. In order to study the gas in inner disks, we …

Be stars possess gaseous circumstellar disks that modify in many ways the spectrum of the
central B star. Furthermore, they exhibit variability at several timescales and for a large …

Aims. The rapidly rotating Be star ϕ Persei was spun up by mass and angular momentum
transfer from a now stripped-down, hot subdwarf companion. Here we present the first high …

Long considered as the “odd man out” among X-ray emitting Be stars, γ Cas (B0. 5e IV) is
now recognized as the prototype of a class of stars that emit hard thermal X-rays. Our …

We analysed V-band photometry of the Be star ω CMa, obtained during the last four
decades, during which the star went through four complete cycles of disc formation and …

ABSTRACT Using observations from Chandra, Swift, and XMM-Newton, we investigate the
high-energy properties of all known (18) Be+ sdO systems as well as seven additional Be …