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arXiv · 1704.08252

Chemical Enhancements in Shock-accelerated Particles: Ab-initio Simulations

Damiano Caprioli·Dennis T. Yi·Anatoly Spitkovsky
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Abstract

We study the thermalization, injection, and acceleration of ions with different mass/charge ratios, $A/Z$, in non-relativistic collisionless shocks via hybrid (kinetic ions-fluid electrons) simulations. In general, ions thermalize to a post-shock temperature proportional to $A$. When diffusive shock acceleration is efficient, ions develop a non-thermal tail whose extent scales with $Z$ and whose normalization is enhanced as $(A/Z)^2$, so that incompletely-ionized heavy ions are preferentially accelerated. We discuss how these findings can explain observed heavy-ion enhancements in Galactic cosmic rays.

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Damiano Caprioli, Dennis T. Yi, Anatoly Spitkovsky. 2017-04-26. Chemical Enhancements in Shock-accelerated Particles: Ab-initio Simulations. https://doi.org/10.1103/physrevlett.119.171101

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