The structure of molecular gas associated with NGC2264: wide-field 12CO and H2 imaging

TL;DR

This study uses wide-field 12CO and H2 imaging to analyze the molecular gas structure in NGC2264, revealing new H2 objects, characterizing cores, and assessing turbulence and outflow impacts in the star-forming region.

Contribution

It provides new wide-field high-resolution imaging data, identifies new H2 emission objects, and analyzes turbulence and outflow effects in NGC2264.

Findings

46 H2 emission objects identified, 35 new discoveries

Protostellar cores are more prevalent, reducing prestellar/protostellar ratio

Turbulence driven on scales >2.6 pc, outflows have limited impact on turbulence

Abstract

We present wide-field, high-resolution imaging observations in 12CO 3-2 and H2 1-0 S(1) towards a ~1 square degree region of NGC2264. We identify 46 H2 emission objects, of which 35 are new discoveries. We characterize several cores as protostellar, reducing the previously observed ratio of prestellar/protostellar cores in the NGC2264 clusters. The length of H2 jets increases the previously reported spatial extent of the clusters. In each cluster, <0.5% of cloud material has been perturbed by outflow activity. A principal component analysis of the 12CO data suggests that turbulence is driven on scales >2.6 pc, which is larger than the extent of the outflows. We obtain an exponent alpha=0.74 for the size-linewidth relation, possibly due to the high surface density of NGC2264. In this very active, mixed-mass star forming region, our observations suggest that protostellar outflow activity is not injecting energy and momentum on a large enough scale to be the dominant source of turbulence.