Analysis of the physical nature of 22 New VVV Survey Globular Cluster candidates in the Milky Way Bulge. (arXiv:1905.11835v1 [astro-ph.GA])
<a href="http://arxiv.org/find/astro-ph/1/au:+Palma_T/0/1/0/all/0/1">Tali Palma</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Minniti_D/0/1/0/all/0/1">Dante Minniti</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Alonso_Garcia_J/0/1/0/all/0/1">Javier Alonso-García</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Crestani_J/0/1/0/all/0/1">Juliana Crestani</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Netzel_H/0/1/0/all/0/1">Henryka Netzel</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Claria_J/0/1/0/all/0/1">Juan J. Clariá</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Saito_R/0/1/0/all/0/1">Roberto K. Saito</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Dias_B/0/1/0/all/0/1">Bruno Dias</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Kammers_R/0/1/0/all/0/1">Roberto Kammers</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Geisler_D/0/1/0/all/0/1">Douglas Geisler</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Gomez_M/0/1/0/all/0/1">Matías Gómez</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Hempel_M/0/1/0/all/0/1">Maren Hempel</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Pullen_J/0/1/0/all/0/1">Joyce Pullen</a>
In order to characterize 22 new globular cluster (GC) candidates in the
Galactic bulge, we present their colour-magnitude diagrams (CMDs) and Ks-band
luminosity functions (LFs) using the near-infrared VVV database as well as
Gaia-DR2 proper motion dataset. CMDs were obtained, on one hand, after properly
decontaminating the observed diagrams from background/foreground disc stars and
other sources. On the other hand, CMDs were also obtained based upon star
selection in proper motion diagrams. Taking into account our deep CMDs and LFs
analyses, we find that 17 out of 22 new GC candidates may be real and should
therefore be followed-up, while 5 candidates were discarded from the original
sample. We also search for RR Lyrae and Mira variable stars in the fields of
these new GC candidates. In particular, we confirm that Minni 40 may be a real
cluster. If confirmed by further follow-up analysis, it would be the closest GC
to the Galactic centre in projected angular distance, located only 0.5 deg away
from it. We consider that it is very difficult to confirm the physical reality
of these small, poorly-populated bulge GCs so in many cases alternative
techniques are needed to corroborate our findings.
In order to characterize 22 new globular cluster (GC) candidates in the
Galactic bulge, we present their colour-magnitude diagrams (CMDs) and Ks-band
luminosity functions (LFs) using the near-infrared VVV database as well as
Gaia-DR2 proper motion dataset. CMDs were obtained, on one hand, after properly
decontaminating the observed diagrams from background/foreground disc stars and
other sources. On the other hand, CMDs were also obtained based upon star
selection in proper motion diagrams. Taking into account our deep CMDs and LFs
analyses, we find that 17 out of 22 new GC candidates may be real and should
therefore be followed-up, while 5 candidates were discarded from the original
sample. We also search for RR Lyrae and Mira variable stars in the fields of
these new GC candidates. In particular, we confirm that Minni 40 may be a real
cluster. If confirmed by further follow-up analysis, it would be the closest GC
to the Galactic centre in projected angular distance, located only 0.5 deg away
from it. We consider that it is very difficult to confirm the physical reality
of these small, poorly-populated bulge GCs so in many cases alternative
techniques are needed to corroborate our findings.
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