R. E. Mennickent, G. Djurasevic, Z. Kolaczkowski, G. Michalska
V393 Scorpii is a bright Galactic Double Periodic Variable showing a long
photometric cycle of approx. 253 days. We present new VIJK photometric time
series for V393 Scorpii along with the analysis of ASAS V-band photometry. We
disentangled all light curves into the orbital and long cycle components. The
ASAS V-band orbital light curve was modeled with two stellar components plus a
circumprimary optically thick disc assuming a semidetached configuration. We
present the results of this calculation, giving physical parameters for the
stars and the disc, along with general system dimensions. Our results are in
close agreement with those previously found by Mennickent et al. (2010) from IR
spectroscopy and the modeling of the spectral energy distribution. The
stability of the orbital light curve suggests that the stellar + disc
configuration remains stable during the long cycle. Therefore, the long cycle
should be produced by an additional variable and not-eclipsed emitting
structure. We discuss the evolutionary stage of the system finding the best
match with one of the evolutionary models of van Rensbergen et al. (2008).
According to these models, the system is found to be after an episode of fast
mass exchange that transferred 4 M_sun from the donor to the gainer in a period
of 400.000 years. We argue that a significant fraction of this mass has not
been accreted by the gainer but remains in an optically thick massive (about 2
M_sun) disc-like surrounding pseudo-photosphere whose luminosity is not driven
by viscosity but probably by reprocessed stellar radiation. Finally, we provide
the result of our search for Galactic Double Periodic Variables and briefly
discuss the outliers beta Lyr and RX Cas.
View original:
http://arxiv.org/abs/1112.2668
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