Exploring the Role of Globular Cluster Specific Frequency on the Nova
  Rates in Three Virgo Elliptical Galaxies
  It has been proposed that a galaxy's nova rate might be enhanced by the
production of nova progenitor binaries in the dense cores of its globular
clusters (GCs). To explore this idea, relative nova rates in three Virgo
elliptical galaxies, M87, M49 and M84, which have significantly different GC
specific frequencies ($S_{N}$) of 14, 3.6, and 1.6, respectively, were measured
over the course of 4 epochs spanning a period of 14 months. To simplify the
analysis, observations of the nearly equidistant galaxies were made on the same
nights, with the same integration times, and through the same filter
(H$\alpha$), so that the relative numbers of novae discovered would reflect the
relative nova rates. At the conclusion of our survey we found a total of 27
novae associated with M87, 37 with M49, and 19 with M84. After correcting for
survey completeness, we found annual nova rates of $154^{+23}_{-19}$,
$189^{+26}_{-22}$, and $95^{+15}_{-14}$, for M87, M49, and M84, respectively,
corresponding to $K$-band luminosity-specific nova rates of $3.8\pm1.0$,
$3.4\pm0.6$, and $3.0\pm0.6$ novae per year per $10^{10}~L_{K,\odot}$. The
overall results of our study suggest that a galaxy's nova rate simply scales
with its luminosity, and is insensitive to its GC specific frequency. Two
novae, one in M87 and one in M84, were found to be spatially coincident with
known GCs. After correcting for the mass fraction in GCs, we estimate that
novae are likely enhanced relative to the field by at least an order of
magnitude in the GC systems of luminous Virgo ellipticals.
