Local H~\sc i emissivity measured with the \it Fermi-LAT and implications for cosmic-ray spectra

2015/05/29 by J. M. Casandjian, Casandjian, Jean-Marc
Physics and Astronomy · #Astrophysics and Cosmic Phenomena #Dark Matter and Cosmic Phenomena #Gamma-ray bursts and supernovae

paper · pdf · doi:10.48550/arxiv.1506.00047

Abstract

Cosmic-ray (CR) electrons and nuclei interact with the Galactic interstellar gas and produce high-energy γ rays. The γ-ray emission rate per hydrogen atom, called emissivity, provides a unique indirect probe of the CR flux. We present the measurement and the interpretation of the emissivity in the solar neighborhood for γ-ray energy from 50~MeV to 50~GeV. We analyzed a subset of 4 years of observations from the Large Area Telescope (LAT) aboard the \it Fermi Gamma-ray Space Telescope (\it Fermi) restricted to absolute latitudes 10^o

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