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arXiv · 1906.08813

High-energy cosmic rays from compact galactic star clusters: particle fluxes and anisotropy

A. M. Bykov·M. E. Kalyashova·D. C. Ellison·S. M. Osipov
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Abstract

It has been shown that supernova blast waves interacting with winds from massive stars in compact star clusters may be capable of producing cosmic-ray (CR) protons to above $10^{17}$ eV. We give a brief description of the colliding-shock-flows mechanism and look at generalizations of the diffusion of ~ 100 PeV CRs in the turbulent galactic magnetic field present in the galactic disk. We calculate the temporal evolution of the CR anisotropy from a possible distribution of young compact massive star clusters assuming the sources are intermittent on time scales of a few million years, i.e., comparable to their residence time in the Milky Way. Within the confines of our model, we determine the galactic/extra-galactic fraction of high-energy CRs resulting in anisotropies consistent with observed values. We find that galactic star clusters may contribute a substantial fraction of ~ 100 PeV CRs without producing anisotropies above observed limits.

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A. M. Bykov, M. E. Kalyashova, D. C. Ellison, S. M. Osipov. 2019-06-20. High-energy cosmic rays from compact galactic star clusters: particle fluxes and anisotropy. https://doi.org/10.1016/j.asr.2019.06.005

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