Star formation around the mid-infrared bubble CN 148

TL;DR

This study investigates star formation around the mid-infrared bubble CN 148, revealing spatially correlated young stellar objects, clusters with age gradients, and signs of triggered star formation influenced by the expanding H II region.

Contribution

It provides a detailed multi-wavelength analysis of star formation processes and the influence of the H II region on the surrounding interstellar medium around CN 148.

Findings

Young stellar objects are spatially correlated with the photodissociation region.

Clusters at the bubble edges are younger than those further away.

Evidence suggests star formation is triggered by the expanding H II region.

Abstract

We present a multi-wavelength study to analyse the star formation process associated with the mid-infrared bubble CN 148 (H II region G10.3-0.1), which harbors an O5V-O6V star. The arc-shaped distribution of molecular CO(2-1) emission, the cold dust emission, and the polycyclic aromatic hydrocarbon features trace a photodissociation region (PDR) around the H II region. We have identified 371 young stellar objects (YSOs) in the selected region and, interestingly, their spatial distribution correlates well with the PDR. 41% of these YSOs are present in 13 clusters, each having visual extinction larger than 16 mag. The clusters at the edges of the bubble (both northeast and southwest) are found to be relatively younger than the clusters located further away from the bubble. We also find that four 6.7 GHz methanol masers, two Extended Green Objects, an ultra-compact H II region, and a massive protostar candidate (as previously reported) are spatially positioned at the edges of the bubble. The existence of an apparent age gradient in YSO clusters and different early evolutionary stages of massive star formation around the bubble suggest their origin to be influenced by an H II region expanding into the surrounding interstellar medium. The data sets are suggestive of triggered star formation.