Abstract:
Optical spectroscopic data of the nova LW Serpentis 1978, covering its diffuse-enhanced phase until the onset of the forbidden O I line flash, were obtained at the Vainu Bappu Observatory, Kavalur, between March 10 and April 7, 1978. Emission lines, covering a range of 4000-8700 A at dispersions ranging from 83-675 A/mm, steadily increased during the observation period, with highest increases for H-alpha and O I 8446 A. A mean absorption velocity of -1303 + or - 46 km/s is deduced, and the present spectral evolution is consistent with those of fast novae such as NQ Vul 1976.