A Deep Search for Faint Chandra X-ray Sources, Radio Sources, and
  Optical Counterparts in NGC 6752
  We report the results of a deep search for faint Chandra X-ray sources, radio
sources, and optical counterparts in the nearby, core-collapsed globular
cluster, NGC 6752. We combined new and archival Chandra imaging to detect 51
X-ray sources (12 of which are new) within the 1.9 arcmin half-light radius.
Three radio sources in deep ATCA 5 and 9 GHz radio images match with Chandra
sources. We have searched for optical identifications for the expanded Chandra
source list using deep Hubble Space Telescope photometry in B, R, H-alpha, UV,
and U. Among the entire sample of 51 Chandra sources, we identify 18
cataclysmic variables (CVs), 9 chromospherically active binaries (ABs), 3 red
giants (RGs), 3 galaxies (GLXs), and 6 active galactic nuclei (AGNs). Three of
the sources are associated with millisecond pulsars (MSPs). As in our previous
study of NGC 6752, we find that the brightest CVs appear to be more centrally
concentrated than are the faintest CVs, although the effect is no longer
statistically significant as a consequence of the inclusion in the faint group
of two intermediate brightness CVs. This possible difference in the radial
distributions of the bright and faint CV groups appears to indicate that mass
segregation has separated them. We note that photometric incompleteness in the
crowded central region of the cluster may also play a role. Both groups of CVs
have an inferred mass above that of the main-sequence turnoff stars. We discuss
the implications for the masses of the CV components.
