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On an extragalactic origin of the dominant part of the hadronic cosmic rays

R. Plaga
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Abstract

The possibility that the major part of all extrasolar hadronic cosmic rays with energies above 10 MeV/n is of extragalactic origin is discussed. Recent observational results on the galactocentric cosmic-ray density gradient and very high gamma-ray emission do not support expectations from the simplest models with a Galactic origin of cosmic rays. The hypothesis that ``flux trapping'' of extragalactical cosmic rays occurs in the Galactic confinement volume is advanced. Taking this phenomenon into account, I explicitely discuss how previous objections against an extragalactic origin of hadronic cosmic rays loose their strength. The local energy density of hadronic cosmic rays and other observational facts can be understood in a very natural way assuming an extragalactical origin. A promising scenario seems to be a Galactic origin of electrons and an extragalactic origin of hadrons.

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R. Plaga. 1997-12-24. On an extragalactic origin of the dominant part of the hadronic cosmic rays. https://arxiv.org/abs/astro-ph/9712321

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