Inspection of 19 globular cluster candidates in the Galactic bulge with
  the VVV survey
  The census of the globular clusters (GCs) in the Milky Way (MW) is still a
work in progress. We explore the nature of 19 new GC candidates in the Galactic
bulge, based on the analysis of their colour-magnitude diagrams (CMDs) in the
near-IR, using the VISTA Variables in the Via L\'actea Survey (VVV) database.
We estimate their main astrophysical parameters: reddening and extinction,
distance, total luminosity, mean cluster proper motions (PMs), metallicity and
age. We obtain the cluster catalogues including the likely cluster members by
applying a decontamination procedure on the observed CMDs, based upon the
vector PM diagrams from VIRAC2. We estimate a wide reddening range of the $0.25
\leqslant E(J-K_s) \leqslant 2.0$ mag and extinction $0.11 \leqslant A_{Ks}
\leqslant 0.86$ mag for the sample clusters as expected in the bulge regions.
The range of heliocentric distances is $6.8\leqslant D\leqslant 11.4$ kpc. This
allows us to place these clusters between 0.56 and 3.25 kpc from the Galactic
centre, assuming $R_{\odot}=8.2$ kpc. Also, their PMs are kinematically similar
to the typical motion of the Galactic bulge, apart from VVV-CL160, which shows
different PMs. We also derive their metallicities and ages, finding $-1.40
\leqslant$ [Fe/H] $\leqslant 0.0$ dex and $t\approx 8-13$ Gyr respectively. The
luminosities are calculated both in $K_{s}-$ and V-bands, recovering $-3.4
\leqslant M_V \leqslant -7.5$. We also examine the possible RR Lyrae members
found in the cluster fields. Based on their positions, kinematics,
metallicities and ages and comparing our results with the literature, we
conclude that 9 candidates are real GCs, 7 need more observations to be fully
confirmed as GCs, whereas 3 candidates are discarded for being younger open
clusters.
