Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Particle acceleration at shock waves: particle spectrum as a function of
  the equation of state of the shocked plasma   We determine the spectrum of particles accelerated at shocks with arbitrary
speed and arbitrary scattering properties for different choices of the equation
of state of the downstream plasma. More specifically we consider the effect of
energy exchange between the electron and proton thermal components downstream,
and the effect of generation of a turbulent magnetic field in the downstream
plasma. The slope of the spectrum turns out to be appreciably affected by all
these phenomena, especially in the Newtonian and trans-relativistic regime,
while in the ultra-relativistic limit the universal spectrum $s\approx 4.3$
seems to be a very solid prediction.

16
The categories of this paper are: stat
2
The categories of this paper are: math
35
The categories of this paper are: mtrl-th
24
The categories of this paper are: dg-ga
5
The categories of this paper are: gr-qc
0
The categories of this paper are: hep-ph
36
The categories of this paper are: cmp-lg
30
The categories of this paper are: q-alg
14
The categories of this paper are: math-ph
8
The categories of this paper are: hep-ex
37
The categories of this paper are: supr-con
10
The categories of this paper are: q-bio
33
The categories of this paper are: plasm-ph
7
The categories of this paper are: hep-th
22
The categories of this paper are: chao-dyn
20
The categories of this paper are: acc-phys