On the new minimum of the symbiotic nova PU Vulpeculae

Abstract

UBV photoelectric photometry covering the period 1989–94 is presented for the symbiotic nova PU Vul together with 3500–7700 Å low-resolution absolute spectro-photometry and high-resolution echelle + CCD profiles of selected emission lines. The discussion is focused on the brightness drop the system experienced between 1993 mid-September and 1994 late-September. As for the first deep minimum in 1980, the interpretation of the new brightness drop remains somewhat unclear. An eclipse of the outbursting component by the cool giant companion may account for several of the observed features, but a few problems remain.