Near-infrared study of new embedded clusters in the Carina complex

TL;DR

This study identifies and characterizes 12 new embedded star clusters in the Carina complex using near-infrared photometry, revealing their ages, distances, and embedded nature, thus enhancing understanding of star formation in this region.

Contribution

The paper reports the discovery and detailed analysis of 12 new embedded clusters in the Carina complex, expanding the known cluster population and providing their astrophysical parameters.

Findings

12 new embedded clusters identified in Carina complex

Clusters have ages up to 4.5 million years

High differential reddening confirms embedded status

Abstract

We analyse the nature of a sample of stellar overdensities that we found projected on the Carina complex. This study is based on 2MASS photometry and involves the photometry decontamination of field stars, elaboration of intrinsic colour-magnitude diagrams J$\times$(J-Ks), colour-colour diagrams (J-H)$\times$(H-Ks) and radial density profiles, in order to determine the structure and the main astrophysical parameters of the best candidates. The verification of an overdensity as an embedded cluster requires a CMD consistent with a PMS content and MS stars, if any. From these results, we are able to verify if they are, in fact, embedded clusters. The results were, in general, rewarding: in a sample of 101 overdensities, the analysis provided 15 candidates, of which three were previously catalogued as clusters (CCCP-Cl$\,$16, Treasure Chest and FSR$\,$1555), and the 12 remaining are discoveries that provided significant results, with ages not above 4.5$\,$Myr and distances compatible with the studied complex. The resulting values for the differential reddening of most candidates were relatively high, confirming that these clusters are still (partially or fully) embedded in the surrounding gas and dust, as a rule within a shell. Histograms with the distribution of the masses, ages and distances were also produced, to give an overview of the results. We conclude that all the 12 newly found embedded clusters are related to the Carina complex.