Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Thermalization Mechanisms in Compact Sources   There is strong observational evidence that a quasi-thermal population of
electrons (or pairs) exists in compact X-ray sources. It is, however, unclear
what mechanism thermalizes the particles. Here, two processes, Coulomb
scattering and synchrotron self-absorption, that may be responsible for the
thermalization, are reviewed. The parameter spaces in which respective process
dominates are given.
  While the Coulomb thermalization mechanism is well-known, this is not the
case for the synchrotron self-absorption thermalization. We give the arguments
that synchrotron self-absorption must act as a thermalizing mechanism in
sufficiently compact sources. The emitting and absorbing electrons then
exchange energy efficiently with the self-absorbed synchrotron radiation field
and are driven towards a relativistic or mildly relativistic thermal
distribution in a few synchrotron cooling times (the "synchrotron boiler").

31
The categories of this paper are: ao-sci
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The categories of this paper are: math-ph
35
The categories of this paper are: mtrl-th
1
The categories of this paper are: cs
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The categories of this paper are: quant-ph
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The categories of this paper are: patt-sol
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The categories of this paper are: hep-th
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The categories of this paper are: cmp-lg
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The categories of this paper are: q-alg
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The categories of this paper are: alg-geom
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The categories of this paper are: nucl-th
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The categories of this paper are: stat
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The categories of this paper are: hep-lat
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The categories of this paper are: acc-phys
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The categories of this paper are: hep-ex
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The categories of this paper are: physics