1999A&A...342L..45V

We present optical R and I photometry of V592 Her obtained one year before its 1998 outburst. We identify V592 Her with a faint blue star, showing variability in R with a standard deviation of ∼0.07mag. With mean quiescent magnitudes of R=21.5 and I=21.4, its outburst amplitude is ∼10mag, which is at the very upper end of the range observed for Tremendous-Outburst-Amplitude Dwarf novae. A main sequence secondary would imply a distance >1500pc, which is inconsistent with the absolute magnitudes in outburst and quiescence expected for a dwarf nova. We conclude that the secondary is a brown dwarf. The quiescent flux is almost completely from the white dwarf, which gives a white dwarf temperature of 10000K and a distance of ∼700pc. The non-detection in a ROSAT PSPC observation implies an upper limit to the X-ray luminosity of ≲4x10³⁰erg/s and to the accretion rate onto the white dwarf of ≲10^–12M_☉/yr.