VVV and DECaPS photometry of the GC Minni 22

DOI

We use deep near-IR photometry of the VISTA Variables in the Via Lactea (VVV) Survey and deep DECam Plane Survey (DECaPS) optical photometry to confirm the physical reality of the candidate globular cluster (GC) Minni 22, which is located in the Galactic bulge. This object, which was detected as a high density region in our maps of bulge red giants, is now confirmed as a real GC based on the optical and near-IR color-magnitude diagrams. We also recover three known fundamental mode (ab type) RR Lyrae stars within 2 arcmin of the cluster center. The presence of RR Lyrae stars also seems to confirm Minni 22 as a bonafide old and metal-poor GC. We estimate a cluster reddening E(J-Ks)=0.6mag and determine its heliocentric distance D=7.4+/-0.3kpc. The optical and near-IR color-magnitude diagrams reveal well-defined red giant branches in all cases, including a red giant branch bump at Ks=13.30+/-0.05mag. The comparison with theoretical isochrones yields a mean metallicity of [Fe/H]=-1.3+/-0.3dex, and age of t~11.2Gyr. This is a good example of a new low-luminosity (M_V_=-6.2mag) GC found in the central bulge of the Milky Way. After discussing the different ways to confirm the existence of bulge GC candidates, we find that one of the best methods is to use the CMDs from the combination of the DECaPS+VVV photometries.

Cone search capability for table J/ApJ/866/12/table2 (The combined VVV-DECaPS multicolor photometry)

Identifier
DOI http://doi.org/10.26093/cds/vizier.18660012
Source https://dc.g-vo.org/rr/q/lp/custom/CDS.VizieR/J/ApJ/866/12
Related Identifier https://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/866/12
Related Identifier http://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/866/12
Metadata Access http://dc.g-vo.org/rr/q/pmh/pubreg.xml?verb=GetRecord&metadataPrefix=oai_b2find&identifier=ivo://CDS.VizieR/J/ApJ/866/12
Provenance
Creator Minniti D.; Schlafly E.F.; Palma T.; Claria J.J.; Hempel M.,Alonso-Garcia J.; Bica E.; Bonatto C.; Braga V.F.; Clementini G.,Garofalo A.; Gomez M.; Ivanov V.D.; Lucas P.W.; Pullen J.; Saito R.K.,Smith L.C.
Publisher CDS
Publication Year 2019
Rights https://cds.unistra.fr/vizier-org/licences_vizier.html
OpenAccess true
Contact CDS support team <cds-question(at)unistra.fr>
Representation
Resource Type Dataset; AstroObjects
Discipline Astrophysics and Astronomy; Natural Sciences; Observational Astronomy; Physics; Stellar Astronomy