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arXiv · 1902.07813

Revealing a new region of gamma-ray emission in the vicinity of HESS J1825-137

M. Araya·A. M. W. Mitchell·R. D. Parsons
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Abstract

HESS J1825-137 is a bright very-high-energy (VHE) gamma-ray source that has been firmly established as a pulsar wind nebula (PWN), and one of the most extended gamma-ray objects within this category. The progenitor supernova remnant (SNR) for this PWN has not been firmly established. We carried out an analysis of gamma-ray observations in the region of HESS J1825-137 with the Fermi-LAT which reveal emission in the direction away from the Galactic plane. The region lies beyond the PWN and reaches a distance from the pulsar compatible with the supposed location of the SNR shock front. The spectrum of the gamma-rays is hard with a photon index of $\sim 1.9$ in the 10-250 GeV range. Several scenarios for the origin of the emission are discussed, including the SNR as a source of high-energy particles and the "leakage"' of leptons from the PWN.

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M. Araya, A. M. W. Mitchell, R. D. Parsons. 2019-02-20. Revealing a new region of gamma-ray emission in the vicinity of HESS J1825-137. https://doi.org/10.1093/mnras%2Fstz462

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