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arXiv · 1110.6644

A new analytic solution for 2nd-order Fermi acceleration

Philipp Mertsch
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Abstract

A new analytic solution for 2nd-order Fermi acceleration is presented. In particular, we consider time-dependent rates for stochastic acceleration, diffusive and convective escape as well as adiabatic losses. The power law index q of the turbulence spectrum is unconstrained and can therefore account for Kolmogorov (q = 5/3) and Kraichnan (q = 3/2) turbulence, Bohm diffusion (q = 1) as well as the hard-sphere approximation (q = 2). This considerably improves beyond solutions known to date and will prove a useful tool for more realistic modelling of 2nd-order Fermi acceleration in a variety of astrophysical environments.

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Philipp Mertsch. 2011-11-23. A new analytic solution for 2nd-order Fermi acceleration. https://doi.org/10.1088/1475-7516%2F2011%2F12%2F010

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