Massive open star clusters using the VVV survey: V. Young clusters with an OB stellar population

• Published in: Astronomy and astrophysics (Berlin) 2016-04, Vol.588, p.A40
• Main Authors: Alegria, S Ramirez, Borissova, J, Chene, A-N, Bonatto, C, Kurtev, R, Amigo, P, Kuhn, M, Gromadzki, M, Carballo-Bello, J A
• Format: Article
• Language: English
• Subjects: Astronomy; Clusters; Galactic bulge; Near infrared radiation; Photometry; Spectroscopy; Stellar age; Stellar populations
• ISSN: 0004-6361; 1432-0746
• DOI: 10.1051/0004-6361/201526618

Context. The ESO public survey VISTA Variables in the Via Lactea (VVV) has contributed with deep multi-epoch photometry of the Galactic bulge and the adjacent part of the disk over 526 sq. deg. More than a hundred cluster candidates have been reported thanks to this survey. Aims. We present the fifth article in a series of papers focused on young and massive clusters discovered in the VVV survey. In this paper, we present the physical characterization of five clusters with a spectroscopically confirmed OB-type stellar population. Methods. To characterize the clusters, we used near-infrared photometry (J, H, and K sub(S)) from the VVV survey and near-infrared K-band spectroscopy from ISAAC at VLT, following the methodology presented in the previous articles of the series. Results. All clusters in our sample are very young (ages between 1-20 Myr), and their total mass are between (1.07 super(+0.40) sub(-0.30))x 10 super(2)M sub([middot in circle]) and (4.17 super(+4.15) sub(-2.08))x 10 super(3)M sub([middot in circle]). We observed a relation between the clusters total mass M sub(ecl) and the mass of their most massive stellar member m sub(max), for clusters with an age