New galactic star clusters discovered in the VVV survey. Candidates projected on the inner disk and bulge

TL;DR

This study reports the discovery of 58 new infrared star cluster candidates in the Milky Way's inner disk and bulge using the VVV survey, with detailed analysis of 20 clusters' parameters.

Contribution

It introduces a new set of 58 obscured star cluster candidates identified through VVV survey data, including detailed characterization of their fundamental parameters.

Findings

Discovered 58 new infrared star cluster candidates.

Determined age, distance, and metallicity for 20 clusters.

Enhanced understanding of star formation in the inner Galaxy.

Abstract

VISTA Variables in the V\'ia L\'actea (VVV) is one of six ESO Public Surveys using the 4 meter Visible and Infrared Survey Telescope for Astronomy (VISTA). The VVV survey covers the Milky Way bulge and an adjacent section of the disk, and one of the principal objectives is to search for new star clusters within previously unreachable obscured parts of the Galaxy. The primary motivation behind this work is to discover and analyze obscured star clusters in the direction of the inner Galactic disk and bulge. Regions of the inner disk and bulge covered by the VVV survey were visually inspected using composite JHKs color images to select new cluster candidates on the basis of apparent overdensities. DR1, DR2, CASU, and PSF photometry of 10x10 arcmin fields centered on each candidate cluster were used to construct color-magnitude and color-color diagrams. Follow-up spectroscopy of the brightest members of several cluster candidates was obtained in order to clarify their nature. We report the discovery of 58 new infrared cluster candidates. Fundamental parameters such as age, distance, and metallicity were determined for 20 of the most populous clusters.