Understanding CV Secondaries and the Energetics of Dwarf Novae Outbursts Via Parallaxes

Abstract

We combine HST and ground-based parallaxes for cataclysmic variables (CVs) to examine their outburst energetics, as well as the nature of their secondary stars. Harrison et al. (2004) have recently published parallaxes for WZ Sge, YZ Cnc, and RU Peg, and have reanalyzed the HST parallaxes for U Gem, SS Aur, and SS Cyg. Combined with existing HST parallaxes for RW Tri (MeArthur et al. 1999), TV Col (MeArthur et al. 2001), EX Hya and V1223 Sgr (Beuermann et al. 2004a,b), ten high-quality parallaxes are available to constrain the various types of outbursts of CVs. In addition, Thorstensen (2003) has published ground-based parallaxes for fourteen CV systems.