A Spectroscopic and Photometric Survey of Novae in M31
  We report the results of a multi-year spectroscopic and photometric survey of
novae in M31 that resulted in a total of 53 spectra of 48 individual nova
candidates. Two of these, M31N 1995-11e and M31N 2007-11g, were revealed to be
long-period Mira variables, not novae. These data double the number of spectra
extant for novae in M31 through the end of 2009 and bring to 91 the number of
M31 novae with known spectroscopic classifications. We find that 75 novae (82%)
are confirmed or likely members of the Fe II spectroscopic class, with the
remaining 16 novae (18%) belonging to the He/N (and related) classes. These
numbers are consistent with those found for Galactic novae. We find no
compelling evidence that spectroscopic class depends sensitively on spatial
position or population within M31 (i.e., bulge vs. disk), although the
distribution for He/N systems appears slightly more extended than that for the
Fe II class. We confirm the existence of a correlation between speed class and
ejection velocity (based on line width), as in the case of Galactic novae.
Follow-up photometry allowed us to determine light-curve parameters for a total
of 47 of the 91 novae with known spectroscopic class. We confirm that more
luminous novae generally fade the fastest, and that He/N novae are typically
faster and brighter than their Fe II counterparts. In addition, we find a weak
dependence of nova speed class on position in M31, with the spatial
distribution of the fastest novae being slightly more extended than that of
slower novae.
