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arXiv · 1404.2104

Power requirements for cosmic ray propagation models involving re-acceleration and a comment on second order Fermi acceleration theory

Andrew Thornbury·Luke O'C. Drury
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Abstract

We derive an analytic expression for the power transferred from interstellar turbulence to the Galactic cosmic rays in propagation models which include re-acceleration. This is used to estimate the power required in such models and the relative importance of the primary acceleration as against re-acceleration. The analysis provides a formal mathematical justification for Fermi's heuristic account of second order acceleration in his classic 1949 paper.

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Andrew Thornbury, Luke O'C. Drury. 2014-05-26. Power requirements for cosmic ray propagation models involving re-acceleration and a comment on second order Fermi acceleration theory. https://doi.org/10.1093/mnras%2Fstu1080

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