Gamma-ray and neutrino diffuse emissions of the Galaxy above the TeV

Abstract

As recently shown, Fermi-LAT measurements of the diffuse gamma-ray emission from the Galaxy favor the presence of a smooth softening in the primary cosmic-ray spectrum with increasing Galactocentric distance. This result can be interpreted in terms of a spatial-dependent rigidity scaling of the diffusion coefficient. The DRAGON code was used to build a model based on such feature. That scenario correctly reproduces the latest Fermi-LAT results as well as local cosmic-ray measurements from PAMELA, AMS-02 and CREAM. Here we show that the model, if extrapolated at larger energies, grasps both the gamma-ray flux measured by MILAGRO at 15 TeV and the H.E.S.S. data from the Galactic ridge, assuming that the cosmic-ray spectral hardening found by those experiments at about 250 GeV/n is present in the whole inner Galactic plane region. Moreover, we show as that model also predicts a neutrino emission which may account for a significant fraction, as well as for the correct spectral shape, of the astrophysical flux measured by IceCube above 25 TeV.

Oral contribution to the 34th International Cosmic Ray Conference, July 30 to August 6, The Hague, Netherlands

References in corpus (7)

• A combined maximum-likelihood analysis of the high-energy astrophysical neutrino flux measured with IceCube
• Discrepant hardening observed in cosmic-ray elemental spectra
• Parameterization of Gamma, e^+/- and Neutrino Spectra Produced by p-p Interaction in Astronomical Environment
• Evidence for Astrophysical Muon Neutrinos from the Northern Sky with IceCube
• The gamma-ray and neutrino sky: A consistent picture of Fermi-LAT, Milagro, and IceCube results
• Search for a diffuse flux of high-energy ${\nu }_{\mu }$ with the ANTARES neutrino telescope
• TeV Neutrinos from SuperNova Remnants embedded in Giant Molecular Clouds