IUE observations of the dwarf nova BV Centauri

The IUE observations of the dwarf nova BV Cen in quiescence are summarized. The reprocessed spectra from January 1979 are analyzed to show that the maximum temperature of the white dwarf primary star, based on its brightness at 1375 A, ranges from 42,000 to about 125,000 K depending upon the adopted values of interstellar reddening, the mass of the white dwarf, and the distance to the system. Physical arguments based on the likely state of the quiescent accretion disk in the BV Cen system suggest that the effective temperature of the white dwarf is significantly lower than this maximum temperature. The disk is more likely to be optically thick than optically thin. The impact of these findings on models for dwarf nova outbursts is discussed, but no firm conclusions can be drawn. The ultraviolet emission-line spectrum from observations obtained in August 1985 is described in detail.