Gamma-Ray Emission Revealed at the Western Edge of SNR G344.7-0.1
Abstract
We report on the investigation of a very high energy (VHE), Galactic γ-ray source recently discovered at >50 GeV using the Large Area Telescope (LAT) on board the Fermi Gamma-ray Space Telescope (Fermi). This object, 2FHL J1703.4-4145, displays a very hard >50 GeV spectrum with a photon index Γγ ∼ 1.2 in the 2FHL catalog and, as such, is one of the most extreme sources in the 2FHL subsample of Galactic objects. A detailed analysis of the available multiwavelength data shows that this source is located on the western edge of the supernova remnant (SNR) G344.7-0.1, along with extended TeV source, HESS J1702-420. The observations and the spectral energy distribution modeling support a scenario where this γ-ray source is the byproduct of the interaction between the SNR shock and the dense surrounding medium, with escaping cosmic rays (CRs) diffusing into the dense environment and interacting with a large local cloud, generating the observed TeV emission. If confirmed, an interaction between the SNR CRs and a nearby cloud would make 2FHL J1703.4-4145 another promising candidate for efficient particle acceleration of the 2FHL Galactic sample, following the first candidate from our previous investigation of a likely shock-cloud interaction occurring on the western edge of the Vela SNR.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- December 2020
- DOI:
- 10.3847/1538-4357/abbe08
- arXiv:
- arXiv:2006.08757
- Bibcode:
- 2020ApJ...904..123E
- Keywords:
-
- High energy astrophysics;
- 1656;
- Astrophysics - High Energy Astrophysical Phenomena
- E-Print:
- 9 pages, 7 figures, Submitted to ApJ June 15, 2020. Accepted for publication Oct 2, 2020