Investigating the morphology and CO gas kinematics of Sh2-112 region

TL;DR

This study investigates the morphology and gas kinematics of the Sh2-112 star-forming region using CO isotopologue data, revealing filamentary structures, cavity features, and evidence of supersonic, non-thermal motions in the molecular cloud.

Contribution

It provides detailed molecular cloud morphology and kinematic analysis of Sh2-112 using CO 3-2 data, highlighting filamentary extensions and cavity structures associated with massive star influence.

Findings

Filamentary extensions directed away from the massive star

Cavity-like structure at the edge of the molecular cloud

Dominance of supersonic, non-thermal motions in the gas

Abstract

We present a study of the molecular cloud in Sh2-112 massive star forming region using the 3-2 transition of CO isotopologues - CO, 13CO, and C18O; supplemented in part by CGPS HI line emission and MSX data. Sh2-112 is an optically visible region powered by an O8V type massive star BD +45 3216, and hosts two Red MSX Survey sources - G083.7962+03.3058 and G083.7071+03.2817 - classified as HII region and young stellar object, respectively. Reduced spectral data products from the James Clerk Maxwell Telescope archive, centered on the two RMS objects with ~7'x7' field of view each, were utilised for the purpose. The 13CO(3-2) channel map of the region shows the molecular cloud to have filamentary extensions directed away from the massive star, which also seems to be at the edge of a cavity like structure. Multiple molecular cloud protrusions into this cavity structure host local peaks of emission. The integrated emission map of the region constructed from only those emission clumps detected above 5$\sigma$ level in the position-position-velocity space affirms the same. MSX sources were found distributed along the cavity boundary where the gas has the been compressed. Spectral extraction at these positions yielded high Mach numbers and low ratios of thermal to non-thermal pressure, suggesting a dominance of supersonic and non-thermal motion in the cloud.