2019 journal article

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

ADVANCES IN SPACE RESEARCH, 64(12), 2439–2444.

author keywords: Acceleration of particles; ISM: cosmic rays; Galactic clusters; Magnetohydrodynamics (MHD); Shock waves; Turbulence
Source: Web Of Science
Added: December 30, 2019

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 1017 eV. We give a brief description of the colliding-shock-flow 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.