Interstellar gas towards CTB 37A and the TeV gamma-ray source HESS J1714-385

TL;DR

This study maps dense molecular gas around supernova remnant CTB 37A and the gamma-ray source HESS J1714-385, supporting hadronic gamma-ray emission and estimating gas masses and cosmic ray enhancements.

Contribution

It provides detailed CO and CS emission maps linking dense gas regions with gamma-ray emission, supporting hadronic origin hypotheses.

Findings

Gas masses estimated at 10^3-10^4 solar masses.

Cosmic ray flux enhancement of 80-1100 times the local value.

Remnant age estimated at approximately 10^4 years.

Abstract

Observations of dense molecular gas towards the supernova remnants CTB 37A (G348.5+0.1) and G348.5-0.0 were carried out using the Mopra and Nanten2 radio telescopes. We present CO(2-1) and CS(1-0) emission maps of a region encompassing the CTB 37A TeV gamma-ray emission, HESS J1714-385, revealing regions of dense gas within associated molecular clouds. Some gas displays good overlap with gamma-ray emission, consistent with hadronic gamma-ray emission scenarios. Masses of gas towards the HESS J1714-385 TeV gamma-ray emission region were estimated, and were of the order of 10^3-10^4 solar masses. In the case of a purely hadronic origin for the gamma-ray emission, the cosmic ray flux enhancement is ~80-1100 times the local solar value. This enhancement factor and other considerations allow a discussion of the age of CTB 37A, which is consistent with ~10^4 yr.