Accretion Disks of Bounce-Back CVs

Abstract

Abstract. We explore conditions and structure of accretion disks in the short-period Cataclysmic Variables, which have evolved beyond the period minimum. We show that the accretion disk in a system with extreme mass ratio grows in the size reaching 2:1 resonance radius and are relatively cool. They also become largely optically thin in the continuum, contributing to the total flux less than the stellar components of the system. In contrast, the viscosity and the temperature in spiral arms formed at the outer edge of the disk are higher and their contribution in continuum plays an increasingly important role. We model such disks and generate light curves which successfully simulate the observed double-humped light curves in the quiescence.

Short Orbital Period Cataclysmic Variables

“…Neustroev et al (2016) proposed that the leading side bright spot is caused by irradiation of tidally thickened sectors of the outer disk. We note that the normal hot spot and the emission structure on the opposite side of the disk can possibly explain double-humped light curves observed in WZ Sge-type stars [43,53].…”