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arXiv · 1505.01236

Can we explain AMS-02 antiproton and positron excesses simultaneously by nearby supernovae without pulsars nor dark matter?

Kazunori Kohri·Kunihito Ioka·Yutaka Fujita·Ryo Yamazaki
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Abstract

We explain the excess of the antiproton fraction recently reported by the AMS-02 experiment by considering collisions between cosmic-ray protons accelerated by a local supernova remnant (SNR) and the surrounding dense cloud. The same "$pp$-collisions" provide the right ratio of daughter particles to fit the observed positron excess simultaneously in the natural model parameters. The supernova happened in relatively lower metalicity than the major cosmic-ray sources. The cutoff energy of electrons marks the supernova age of $\sim 10^{5}$ years, while the antiproton excess may extend to higher energy. Both antiproton and positron fluxes are completely consistent with our predictions in Fujita, Kohri, Yamasaki and Ioka (2009).

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Kazunori Kohri, Kunihito Ioka, Yutaka Fujita, Ryo Yamazaki. 2015-05-06. Can we explain AMS-02 antiproton and positron excesses simultaneously by nearby supernovae without pulsars nor dark matter?. https://doi.org/10.1093/ptep%2Fptv193

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