IR Geminorum : indications of a massive white dwarf and a heated secondary in this new SU Ursae Majoris cataclysmic variable.

Abstract

We report the discovery of a new SU UMa type cataclysmic variable through confirmation of a 102 minute superhump period during a supermaximum. The superhump has a 30% color-independent amplitude with a decrease in the equivalent widths of the Balmer absorption lines. Spectroscopic and photometric studies during quiescence show a 98-101 minute orbital period with evidence for heating of the secondary star. The flux distribution from 0.1 to 1.25 μ m fits with a 20,000 K heated blackbody (or an M = 10^-9 M _sun yr^-1 Williams and Ferguson accretion disk model). The low semiamplitude of the radial velocity curve implies a high mass white dwarf and possibly a degenerate secondary, but may be complicated by an unresolved component in the emission lines.