The interacting binary V393 Scorpii: another clue for Double Periodic Variables

We give a brief report on spectroscopic properties of V 393 Scorpii. Hα emission and shape and radial velocity of He I 5875 are modulated with the long cycle. The long cycle is explained as a relaxation cycle in the circumprimary disc, that cumulates the mass transferred from the donor until certain instability produces disc depletion.