Evidence for Unresolved γ-Ray Point Sources in the Inner Galaxy.
| Authors | |
| Abstract | We present a new method to characterize unresolved point sources (PSs) generalizing traditional template fits to account for non-Poissonian photon statistics. We apply this method to Fermi Large Area Telescope γ-ray data to characterize PS populations at high latitudes and in the Inner Galaxy. We find that PSs (resolved and unresolved) account for ∼50% of the total extragalactic γ-ray background in the energy range ∼1.9 to 11.9 GeV. Within 10° of the Galactic Center with |b|≥2°, we find that ∼5%-10% of the flux can be accounted for by a population of unresolved PSs distributed consistently with the observed ∼GeV γ-ray excess in this region. The excess is fully absorbed by such a population, in preference to dark-matter annihilation. The inferred source population is dominated by near-threshold sources, which may be detectable in future searches. |
| Year of Publication | 2016
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| Journal | Phys Rev Lett
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| Volume | 116
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| Issue | 5
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| Pages | 051103
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| Date Published | 2016 Feb 05
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| ISSN | 1079-7114
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| URL | |
| DOI | 10.1103/PhysRevLett.116.051103
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| PubMed ID | 26894697
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