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Sgr A East as a possible high energy neutron factory in the Galactic Centre

Dario Grasso·Luca Maccione
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Abstract

Sgr A East is a supernova remnant located within few parsecs from the Galactic Centre (GC). There are good reasons to believe that this object is the source of the gamma-ray excess detected by HESS in the direction of the GC meaning that Sgr A East is likely to be an efficient Cosmic Ray accelerator. Some observations suggest that strong magnetic fields may be present in that region allowing the acceleration of composite nuclei in Sgr A East beyond the EeV. We show that, if this is case, EeV neutrons should be effectively produced by the photo-disintegration of Ultra High Energy nuclei onto the IR photon background (with temperature $\sim 40$ K) in which Sgr A East is embedded. Neutrons with such an energy can reach the Earth before decaying and may be detectable under the form of a CR point-like excess in the direction of the GC. We determine the expected energy spectrum and the amplitude of this signal showing that it may be measurable by the AUGER observatory.

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Dario Grasso, Luca Maccione. 2005-07-28. Sgr A East as a possible high energy neutron factory in the Galactic Centre. https://doi.org/10.1016/j.astropartphys.2005.07.005

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