ON THE MASS OF NOVA DQ HERCULIS (1934)

Published estimates of the white dwarf mass in the moderately slow nov a DQ Her range from 0.35 to 1.2 M.. We report new estimates of the ste llar masses, M1 = 0.60 +/- 0.07 M. and M2 = 0.40 +/- 0.05 M., and othe r system parameters as given in Table 2. These estimates are based on time-resolved 1.6 angstrom resolution CCD spectroscopy of Na I lambdal ambda8183, 8195 absorption from the secondary star of DQ Her. We measu re a radial velocity curve with K(obs) = 232 +/- 5 km s-1 and rotation al broadening V(rot) sin i = 115 +/- 18 km s-1. We correct K(obs) to K 2 = 227 +/- 10 km s-1 to take account of irradiation effects. The new estimate of M1 is an important parameter for thermonuclear runaway mod els of the nova eruption that occurred in 1934.