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تسجيل مستخدم جديدThe interacting binary V 393 Scorpii: another clue for Double Periodic Variables
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We give a brief report on spectroscopic properties of V 393 Scorpii. H alfa 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.
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V393 Scorpii is a Double Periodic Variable characterized by a relatively stable non-orbital photometric cycle of 253 days. Mennickent et al. argue for the presence of a massive optically thick disc around the more massive B-type component and describ
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