On the Enhanced Mass Outflow during Dwarf Nova Outbursts

During dwarf nova outbursts the secondary component is irradiated by the boundary layer and the white dwarf. The problem is whether the hotter material from irradiated regions can reach the vicinity of the inner Lagrangian point L1, producing an enhanced mass outflow. Osaki and Meyer (2003, 2004) presented a model in which the pressure gradient in the direction towards L1 is always exactly balanced by the Coriolis force and, consequently, does not produce any acceleration and motion in that direction. Instead the material is predicted to flow in the perpendicular direction along the shadow boundary. It is shown that this model, as based on an arbitrary assumption, is incorrect. My model (Smak 2004) produced flow trajectories directed (due to the pressure gradient) toward the equator, but deflected (due to the Coriolis force) with respect to the direction toward L1. In systems with short orbital periods the effects of the Coriolis force were not large enough, however, to prevent the material from reaching L1. Criticism of this model by Osaki and Meyer (2004), concerning incomplete treatment of the equation of continuity, is shown to result primarily from misunderstandings.