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arXiv · 1504.02477

Young Pulsars and the Galactic Center GeV Gamma-ray Excess

Ryan M. O'Leary·Matthew D. Kistler·Matthew Kerr·Jason Dexter
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Abstract

Studies of Fermi data indicate an excess of GeV gamma rays around the Galactic center (GC), possibly due to dark matter. We show that young gamma-ray pulsars can yield a similar signal. First, a high concentration of GC supernovae naturally leads to a population of kicked pulsars symmetric about the GC. Second, while very-young pulsars with soft spectra reside near the Galactic plane, pulsars with spectra that have hardened with age accumulate at larger angles. This combination, including unresolved foreground pulsars, traces the morphology and spectrum of the Excess.

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Ryan M. O'Leary, Matthew D. Kistler, Matthew Kerr, Jason Dexter. 2015-04-09. Young Pulsars and the Galactic Center GeV Gamma-ray Excess. https://arxiv.org/abs/1504.02477

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