Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: On the Early Stage of Nucleus--Nucleus Collisions   A statistical model of the early stage of central nucleus--nucleus (A+A)
collisions is developed. We suggest a description of the confined state with
several free parameters fitted to a compilation of A+A data at the AGS. For the
deconfined state a simple Bag model equation of state is assumed. The model
leads to the conclusion that a Quark Gluon Plasma is created in central
nucleus--nucleus collisions at the SPS. This result is in quantitative
agreement with existing SPS data on pion and strangeness production and gives a
natural explanation for their scaling behaviour. The localization and the
properties of the transition region are discussed. It is shown that the
deconfinement transition can be detected by observation of the characteristic
energy dependence of pion and strangeness multiplicities, and by an increase of
the event--by--event fluctuations. An attempt to understand the data on J/psi
production in Pb+Pb collisions at the SPS within the same approach is
presented.

27
The categories of this paper are: comp-gas
37
The categories of this paper are: supr-con
15
The categories of this paper are: nucl-ex
32
The categories of this paper are: atom-ph
18
The categories of this paper are: econ
9
The categories of this paper are: nlin
29
The categories of this paper are: funct-an
6
The categories of this paper are: astro-ph
21
The categories of this paper are: adap-org
1
The categories of this paper are: cs
36
The categories of this paper are: cmp-lg
34
The categories of this paper are: chem-ph
35
The categories of this paper are: mtrl-th
33
The categories of this paper are: plasm-ph
20
The categories of this paper are: acc-phys
10
The categories of this paper are: q-bio