SPECTROSCOPY OF THE RECURRENT NOVA-V3890 SAGITTARII-18D AFTER THE 1990 OUTBURST

The spectrum of the recurrent nova V3890 Sgr, obtained from the Vainu Bappu Observatory 18 d after the 1990 outburst maximum, is presented. The nova was in the coronal line phase. The spectrum is similar to that of the recurrent nova RS Oph. An extinction E(B-V) = 1.1 is derived from the B-V colours, and from Balmer and He I line ratios. From the maximum magnitude-rate-of-decline relations for a nova, M(V) = -8.6 mag is estimated, which places the nova at a distance of about 5 kpc. Balmer fine fluxes are used to derive the density, approximately 10(9) cm-3, and the mass of the ejected ionized shell, approximately 10(-7) M.. The temperature and radius estimates for the ionizing source are 3 X 10(5) K and 0.06 R.. A helium abundance of 0.23 is estimated.