084031

gamma Cas stars are Oe-Be stars that display an intriguing bright and hard X-ray emission. The origin of this X-ray emission could be either accretion by a compact companion or an interaction between the Be star and its decretion disk. Evidence favouring the latter scenario was obtained over recent years. This includes observations of a quasi-simultaneous decrease by a factor 10 of the X-ray emission of HD45314 as the disk of this star nearly dissipated in 2016. We aim at further constraining the gamma Cas phenomenon by taking advantage of such spectacular variations. For this purpose comma we propose observing a gamma Cas star next time that its disk undergoes either an outburst or in case it clears away.