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arXiv · 1008.1840

Gamma-ray Emission from Crushed Clouds in Supernova Remnants

Yasunobu Uchiyama·Roger Blandford·Stefan Funk·Hiroyasu Tajima·Takaaki Tanaka
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Abstract

It is shown that the radio and gamma-ray emission observed from newly-found "GeV-bright" supernova remnants (SNRs) can be explained by a model, in which a shocked cloud and shock-accelerated cosmic rays (CRs) frozen in it are simultaneously compressed by the supernova blastwave as a result of formation of a radiative cloud shock. Simple reacceleration of pre-existing CRs is generally sufficient to power the observed gamma-ray emission through the decays of neutral pions produced in hadronic interactions between high-energy protons (nuclei) and gas in the compressed-cloud layer. This model provides a natural account of the observed synchrotron radiation in SNRs W51C, W44 and IC 443 with flat radio spectral index, which can be ascribed to a combination of secondary and reaccelerated electrons and positrons.

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Yasunobu Uchiyama, Roger Blandford, Stefan Funk, Hiroyasu Tajima, Takaaki Tanaka. 2010-09-30. Gamma-ray Emission from Crushed Clouds in Supernova Remnants. https://doi.org/10.1088/2041-8205%2F723%2F1%2Fl122

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