This content will become publicly available on June 1, 2023
 Award ID(s):
 1655280
 Publication Date:
 NSFPAR ID:
 10355939
 Journal Name:
 The Astrophysical Journal
 Volume:
 932
 Issue:
 1
 Page Range or eLocationID:
 65
 ISSN:
 0004637X
 Sponsoring Org:
 National Science Foundation
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Abstract Subsonic, compressive turbulence transfers energy to cosmic rays (CRs), a process known as nonresonant reacceleration. It is often invoked to explain the observed ratios of primary to secondary CRs at ∼GeV energies, assuming wholly diffusive CR transport. However, such estimates ignore the impact of CR selfconfinement and streaming. We study these issues in stirring box magnetohydrodynamic (MHD) simulations using Athena++, with fieldaligned diffusive and streaming CR transport. For diffusion only, we find CR reacceleration rates in good agreement with analytic predictions. When streaming is included, reacceleration rates depend on plasma
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