Study of the very high energy gamma-ray spectrum from the Galactic Center and future prospects
arXiv:1610.10003 · doi:10.1103/PhysRevD.94.103005
Abstract
Ground-based gamma ray observations of the Galactic Center region have revealed a high energy gamma ray source spatially coincident with the gravitational centroid of our Galaxy. The pointlike emission detected by H.E.S.S. exhibits an energy cut-off at about 10 TeV. We identify the parameters of the best fit of the exponential and the super-exponential cutoff models to the spectrum of the pointlike source and find that super-exponential one provides a similar quality of the fit to the spectrum of the pointlike source as the best-fit exponential cutoff model, while a dark matter interpretation does not provide as good a fit in the whole energy range of the signal. Based on the magnitude of the flux we derive constraints in the plane of the slope of the density profile and the critical radius, below which the density is assumed to be constant, . Motivated by recent results on the spectrum and morphology from H.E.S.S. and by the possible observation of a super-exponential cutoff, we forecast the observations of super-exponential versus exponential cut-offs by the upcoming Cherenkov Telescope Array (CTA). We derive a formula for -factor in the small angle approximation and propose approximate morphological constraints on the central source.
10 pages, 7 figures; accepted for publication in PRD
References in corpus (4)
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- Dark matter dynamics in Galactic center
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