A wind accretion wake in RW Hydrae?

RW Hydrae is an eclipsing detached binary star system, consisting of a mass losing M-giant and a hot white dwarf on circular orbits. We analyze UV obs ervations of RW Hydrae. Approximately at phi = 0.78, clearly unrelated to t he primary eclipse. we detect in the UV light curve an event with significa ntly reduced UV flux. The spectral characteristics of this event indicate R ayleigh scattering due to a high column density of neutral hydrogen in the line of sight to the hot white dwarf. We model this observation in the framework of an accretion wake trailing th e white dwarf. This interpretation is analogous to comparable models for ze ta Aur systems and X-ray binaries. We find qualitative agreement between ou r 3D hydrodynamical, accretion simulation and the observed UV light curve o f RW Hya.