Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Understanding of the freeze-out in ultra-relativistic heavy-ion
  collisions   I discuss the quantities and effects important for the freeze-out and outline
a formalism for the description of continuous decoupling of particles from the
fireball. Then I present a calculation of the scattering rates of pions at
various temperatures and argue that it is important to take continuous particle
decoupling into account when modelling the collision dynamics.

20
The categories of this paper are: acc-phys
24
The categories of this paper are: dg-ga
5
The categories of this paper are: gr-qc
28
The categories of this paper are: alg-geom
22
The categories of this paper are: chao-dyn
6
The categories of this paper are: astro-ph
26
The categories of this paper are: bayes-an
3
The categories of this paper are: physics
17
The categories of this paper are: q-fin
15
The categories of this paper are: nucl-ex
30
The categories of this paper are: q-alg
36
The categories of this paper are: cmp-lg
7
The categories of this paper are: hep-th
21
The categories of this paper are: adap-org
23
The categories of this paper are: solv-int
37
The categories of this paper are: supr-con