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arXiv · 1109.0834

Systematic effects in the estimate of the local gamma-ray emissivity

Timur Delahaye·Pierre Salati·Armand Fiasson·Martin Pohl
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Abstract

We show in this letter that estimates of the local emissivity of {\gamma}-rays in the GeV-TeV range suffer uncertainties which are of the same order of magnitude as the current Fermi results. Primary cosmic-ray fluxes, cosmic-ray propagation, interstellar helium abundance and {\gamma}-ray production crosssections all affect the estimate of this quantity. We also show that the so-called nuclear enhancement factor -- though widely used so far to model the {\gamma}-ray emissivity -- is no longer a relevant quantity given the latest measurements of the primary cosmic ray proton and helium spectra.

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Timur Delahaye, Pierre Salati, Armand Fiasson, Martin Pohl. 2011-09-05. Systematic effects in the estimate of the local gamma-ray emissivity. https://arxiv.org/abs/1109.0834

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