The Next Generation Virgo Cluster Survey. VIII. The Spatial Distribution
  of Globular Clusters in the Virgo Cluster
  We report on a large-scale study of the distribution of globular clusters
(GCs) throughout the Virgo cluster, based on photometry from the Next
Generation Virgo Cluster Survey, a large imaging survey covering Virgo's
primary subclusters to their virial radii. Using the g', (g'-i')
color-magnitude diagram of unresolved and marginally-resolved sources, we
constructed 2-D maps of the GC distribution. We present the clearest evidence
to date showing the difference in concentration between red and blue GCs over
the extent of the cluster, where the red (metal-rich) GCs are largely located
around the massive early-type galaxies, whilst the blue (metal-poor) GCs have a
more extended spatial distribution, with significant populations present beyond
83' (215 kpc) along the major axes of M49 and M87. The GC distribution around
M87 and M49 shows remarkable agreement with the shape, ellipticity and boxiness
of the diffuse light surrounding both galaxies. We find evidence for spatial
enhancements of GCs surrounding M87 that may be indicative of recent
interactions or an ongoing merger history. We compare the GC map to the
locations of Virgo galaxies and the intracluster X-ray gas, and find good
agreement between these baryonic structures. The Virgo cluster contains a total
population of 67300$\pm$14400 GCs, of which 35% are located in M87 and M49
alone. We compute a cluster-wide specific frequency S_N,CL=$2.8\pm0.7$,
including Virgo's diffuse light. The GC-to-baryonic mass fraction is
e_b=$5.7\pm1.1\times10^{-4} $and the GC-to-total cluster mass formation
efficiency is e_t=$2.9\pm0.5\times10^{-5}$, values slightly lower than, but
consistent with, those derived for individual galactic halos. Our results show
that the production of the complex structures in the unrelaxed Virgo cluster
core (including the diffuse intracluster light) is an ongoing
process.(abridged)
