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arXiv · 1811.05898

2FHL J0826.1-4500: Discovery of a possible shock-cloud interaction on the Western edge of the Vela SNR

Jordan Eagle·Stefano Marchesi·Daniel Castro·Marco Ajello·Laura Duvidovich·Luigi Tibaldo
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Abstract

We report on the investigation of a very high energy (VHE), Galactic gamma-ray source recently discovered at >50GeV using the Large Area Telescope (LAT) on board the Fermi-LAT. This object, 2FHL J0826.1-4500, displays one of the hardest >50GeV spectra (gamma-ray photon index ~1.6) in the 2FHL catalog, and a follow-up observation with XMM-Newton has uncovered diffuse, soft thermal emission at the position of the gamma-ray source. A detailed analysis of the available multi-wavelength data shows that this source is located on the Western edge of the Vela supernova remnant (SNR): the observations and the spectral energy distribution modelling support a scenario where this gamma-ray source is the byproduct of the interaction between the SNR shock and a neutral Hydrogen cloud. If confirmed, this shock-cloud interaction would make 2FHL J0826.1-4500 a promising candidate for efficient particle acceleration.

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Jordan Eagle, Stefano Marchesi, Daniel Castro, Marco Ajello, Laura Duvidovich, Luigi Tibaldo. 2018-11-14. 2FHL J0826.1-4500: Discovery of a possible shock-cloud interaction on the Western edge of the Vela SNR. https://doi.org/10.3847/1538-4357%2Faaf0ff

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