FH Leonis, the first dwarf nova member of a multiple star system?

Abstract

Aims. Sudden brightenings of HD 96273 or BD+07 2411B were observed with the HIPPARCOS satellite in 1992, which still require a convincing explanation. Methods. A new analysis of all known data of these two stars is given, including additional information on the Balmer line equivalent widths. Results. The brightenings can be explained as SU UMa type dwarf nova outbursts, superimposed on the combined light of two normal F and G type main sequence stars. Since the hypothetical dwarf nova turns out to be located at the same distance as HD 96273 and BD+07 2411B, we possibly see here the first case of a cataclysmic variable as a member of a multiple star system. Questions on history and evolution, as well as possible ways to confirm this interpretation, are briefly outlined. © ESO 2006.