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arXiv · 1905.06699

Origin of hardening and universality of cosmic rays spectra in GV-PV rigidity region

A A Lagutin·N V Volkov·R I Raikin·A G Tyumentsev
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Abstract

Recent balloon-borne and satellite experiments have established new features in the behavior of the spectra of cosmic rays. An analysis of all the data showed that hardening of most abundant primary cosmic ray nuclei spectra with increasing rigidity is observed in $>200$ GV region. At the same time, rigidity dependencies of secondary cosmic rays are distinctly different. The AMS-02 data show that above 200 GV the secondary cosmic rays Li, Be, B harden more than the primary He, C, O. In this paper we discuss a new scenario that self-consistently describes these new features of the cosmic ray spectra. We demonstrate that the measured by the AMS-02 changes in the slope of the cosmic ray spectra caused by the transition from the contribution of multiple distant Galactic sources, including the nuclear interactions of the particles accelerated by these sources with an interstellar medium during their wandering in the Galaxy, to the contribution of mainly local ones. We also found that the spectral universality is observed at rigidity $R> 10^5$ GV.

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A A Lagutin, N V Volkov, R I Raikin, A G Tyumentsev. 2019-05-16. Origin of hardening and universality of cosmic rays spectra in GV-PV rigidity region. https://doi.org/10.1088/1742-6596%2F1181%2F1%2F012023

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