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arXiv · 1108.1023

Testing the Origin of High-Energy Cosmic Rays

Andrey E. Vladimirov·Guðlaugur Jóhannesson·Igor V. Moskalenko·Troy A. Porter
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Abstract

Recent accurate measurements of cosmic-ray (CR) protons and nuclei by ATIC-2, CREAM, and PAMELA reveal: a) unexpected spectral hardening in the spectra of CR species above a few hundred GeV per nucleon, b) a harder spectrum of He compared to protons, and c) softening of the CR spectra just below the break energy. These newly-discovered features may offer a clue to the origin of the observed high-energy Galactic CRs. We discuss possible interpretations of these spectral features and make predictions for the secondary CR fluxes and secondary to primary ratios, anisotropy of CRs, and diffuse Galactic {\gamma}-ray emission in different phenomenological scenarios. Our predictions can be tested by currently running or near-future high-energy astrophysics experiments.

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Andrey E. Vladimirov, Guðlaugur Jóhannesson, Igor V. Moskalenko, Troy A. Porter. 2011-08-04. Testing the Origin of High-Energy Cosmic Rays. https://doi.org/10.1088/0004-637x/752/1/68

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