Three Galactic globular cluster candidates
  The census of Galactic globular clusters (GCs) is still incomplete, and about
ten new objects are supposed to await discovery, hidden behind the crowded and
reddened regions of the Galactic bulge and disk. We investigated the nature of
three new GC candidates, discovered in the frames collected by the Vista
Variables in the Via Lactea (VVV) near-infrared survey. They will be called VVV
CL002, VVV CL003, and VVV CL004. We studied the results of
point-spread-function near-infrared photometry from VVV data for the three
objects and their surrounding fields, the proper motion information available
in the literature and, when possible, we derived the cluster parameters by
means of calibrated indices measured on the color-magnitude diagrams. The
evidence shows that VVV CL002 is a newly discovered, small, moderately
metal-rich (Fe/H -0.4) Galactic GC. It is located at a Galactocentric distance
of 0.7+-0.9 kpc, and it could be one of the nearest GC to the Galactic center.
Its characteristics are more similar to those of low-mass, Palomar-like GCs
than to more classical, old, and massive bulge GCs. VVV CL003 is the first star
cluster discovered in the Galactic disk on the opposite side of the center with
respect to the Sun, at a Galactocentric distance of ~5 kpc. Its high
metallicity (Fe/H -0.1) and location point to an open cluster, but a GC cannot
be excluded. VVV CL004, on the contrary, is most probably only a random clump
of field stars, as indicated by both its low statistical significance and by
the impossibility to distinguish its stars from the surrounding field
population. We claim the detection of i) a new Galactic GC, deriving an
estimate of its basic parameters; ii) a stellar aggregate, probably an open
cluster, in the disk directly beyond the Galactic center; and iii) an
overdensity of stars, most probably an asterism.
