A Near-Infrared Study of the Stellar Cluster: [DBS2003] 45

TL;DR

This study characterizes the stellar cluster [DBS2003] 45 using multi-wavelength photometry and spectroscopy, revealing its age, mass, stellar content, and associated ionized gas bubble, and suggesting triggered star formation at its periphery.

Contribution

It provides the first detailed multi-wavelength analysis of [DBS2003] 45, including age, mass function, and star formation activity, which were not previously characterized.

Findings

Cluster age estimated between 5 and 8 Myr.

Mass function slope consistent with Salpeter value.

Associated ionized gas bubble with triggered star formation.

Abstract

We present a multi-wavelength photometric and spectroscopic study of a newly discovered candidate cluster [DBS2003] 45. Our H, Ks photometry confirms that [DBS2003] 45 is a cluster. An average visual extinction Av 7.1+/-0.5 is needed to fit the cluster sequence with a model isochrone. Low resolution spectroscopy indicates that half a dozen early B and at least one late O type giant stars are present in the cluster. We estimate the age of the cluster to be between 5 and 8 Myr based on spectroscopic analysis. Assuming an age of 6 Myr, we fit the observed mass function with a power law, N(M) M^(-Gamma), and find an index Gamma 1.27+/-0.15, which is consistent with the Salpeter value. We estimate the total cluster mass is around 1000 solar masses by integrating the derived mass function between 0.5 and 45 solar masses. Both mid-infrared and radio wavelength observations show that a bubble filled with ionized gas is associated with the cluster. The total ionizing photon flux estimated from radio continuum measurements is consistent with the number of hot stars we detected. Infrared bright point sources along the rim of the bubble suggest that there is triggered star formation at the periphery of the HII region.