Observing two dark accelerators around the Galactic Centre with Fermi Large Area Telescope

Abstract

We report the results from a detailed $\gamma -$ray investigation in the field of two "dark accelerators", HESS J1745-303 and HESS J1741-302, with $6.9$ years of data obtained by the Fermi Large Area Telescope. For HESS J1745-303, we found that its MeV-GeV emission is mainly originated from the "Region A" of the TeV feature. Its $\gamma -$ray spectrum can be modeled with a single power-law with a photon index of $\Gamma \sim 2.5$ from few hundreds MeV to TeV. Moreover, an elongated feature, which extends from "Region A" toward northwest for $\sim 1.3^{\circ }$, is discovered for the first time. The orientation of this feature is similar to that of a large scale atomic/molecular gas distribution. For HESS J1741-302, our analysis does not yield any MeV-GeV counterpart for this unidentified TeV source. On the other hand, we have detected a new point source, Fermi J1740.1-3013, serendipitously. Its spectrum is apparently curved which resembles that of a $\gamma -$ray pulsar. This makes it possibly associated with PSR B1737-20 or PSR J1739-3023.

arXiv comment11 pages, 7 figures, 2 tables, accepted for publication in MNRAS

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• Exploring the dark accelerator HESS J1745-303 with Fermi Large Area Telescope
• Molecular and Atomic Gas toward HESS J1745-303 in the Galactic Center: Further Support for the Hadronic Scenario
• Multi-wavelength study of HESS J1741-302

Cited by in corpus (10)

• Search for extended sources in the Galactic Plane using 6 years of Fermi-Large Area Telescope Pass 8 data above 10 GeV
• Uniform distribution of the extremely overionized plasma associated with the supernova remnant G359.1-0.5
• Observational constraints on the maximum energies of accelerated particles in supernova remnants: low maximum energies and a large variety
• Study on the escape timescale of high-energy particles from supernova remnants through thermal X-ray properties
• HESS J1741-302: a hidden accelerator in the Galactic plane
• HESS J1427-608: an unusual hard unbroken $\gamma -$ray spectrum in a very wide energy range
• Studying the SGR 1806-20/Cl* 1806-20 region using the \emph{Fermi} Large Area Telescope
• Molecular environments of the supernova remnant G359.1-0.5
• One of Everything: The Breakthrough Listen Exotica Catalog
• Exploring the possible gluon condensation signature in gamma-ray emission from pulsars