Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Time Evolution of Fast Particles During the Decay of Hadronic Systems   A phenomenological model is presented based on the formation of nuclear
thermodynamic system during the collision of heavy ions in the regime of
intermediate and high energy regions. The formulation and the dynamic picture
are determined by solving the Vlasov equation. The solution is dressed in the
form of a power series. The first term of which is the equilibrium distribution
in phase space. The rest, are time dependent perturbation terms due to the
multiple strong interactions inside the system. The temperature gradient and
the derivatives of the phase function are calculated. The time dependence of
the angular emission of the produced particles is studied. It is found that
particles emitted in the forward direction are produced in the early stage of
the reaction, far from the equilibrium. Backward production comes in a later
stage when the system constituents undergo multiple cascade collisions.

36
The categories of this paper are: cmp-lg
26
The categories of this paper are: bayes-an
33
The categories of this paper are: plasm-ph
34
The categories of this paper are: chem-ph
7
The categories of this paper are: hep-th
12
The categories of this paper are: nucl-th
27
The categories of this paper are: comp-gas
37
The categories of this paper are: supr-con
32
The categories of this paper are: atom-ph
23
The categories of this paper are: solv-int
4
The categories of this paper are: cond-mat
21
The categories of this paper are: adap-org
2
The categories of this paper are: math
19
The categories of this paper are: eess
11
The categories of this paper are: hep-lat
8
The categories of this paper are: hep-ex