High energy emission from the Galactic Center: Theory and observations
1 ISDC Data Centre for Astrophysics
2 Dublin City University
3 Dublin Institute for Advanced Studies
Published online: 8 December 2015
Galactic Centre is a bright γ-ray source with the GeV-TeV band spectrum composed of two distinct components in the 1–10 GeV and 1–10 TeV energy ranges. The nature of the two components is not clearly understood. We report the analysis of the data of 74 months of observations of the Galactic Center by Fermi/LAT γ-ray telescope with the goal to constrain the morphology of the source and the nature of the two components. Spatially the Galactic Center is consistent with a point source with 0.13∘ 3σ upper limit on its radius. We use the Fermi/LAT data in the energy band below 100 MeV to show that the γ-ray emission from the Galactic Centre source can't be explained within the pure hadronic model and discuss the necessary modifications to make the model to be consistent with the observational data. We also discuss an alternative self-consistent interpretation of the 60 MeV–30 TeV spectrum of the source by a model in which the signal is produced via inverse Compton scattering of the ambient infrared radiation field.
© Owned by the authors, published by EDP Sciences, 2015
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