Dwarf Novae with Newly Determined Parallaxes: Model Analyses of VY Aquari, RU Pegasi, and T Leonis

Abstract

Using newly determined parallaxes for dwarf novae, we have derived outburst accretion rates for VY Aqr, RU Peg and T Leo and for T Leo during quiescence. The two short-period dwarf novae, VY Aqr and T Leo, show good agreement with optically thick steady-state accretion disks in outburst, whereas RU Peg shows a significant departure from a steady-state disk. We have determined that the white dwarf in T Leo has T${}_{eff}=16,000\pm 1000$ K, a value consistent with long term compressional heating when gravitational wave emission drives mass transfer. The white dwarf in T Leo has a temperature in the same narrow range as other WZ Sge-like dwarf novae.

The paper will apear in the October, 2004 issue of PASP