Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The nuclear equation of state probed by $K^+$ production in heavy ion
  collisions   The dependence of $K^+$ production on the nuclear equation of state is
investigated in heavy ion collisions. An increase of the excitation function of
$K^+$ multiplicities obtained in heavy ($Au+Au$) over light ($C+C$) systems
when going far below threshold which has been observed by the KaoS
Collaboration strongly favours a soft equation of state. This observation holds
despite of the influence of an in-medium kaon potential predicted by effective
chiral models which is necessary to reproduce the experimental $K^+$ yields.
Phase space effects are discussed with respect to the $K^+$ excitation
function.

18
The categories of this paper are: econ
8
The categories of this paper are: hep-ex
22
The categories of this paper are: chao-dyn
2
The categories of this paper are: math
28
The categories of this paper are: alg-geom
35
The categories of this paper are: mtrl-th
37
The categories of this paper are: supr-con
21
The categories of this paper are: adap-org
23
The categories of this paper are: solv-int
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The categories of this paper are: q-fin
7
The categories of this paper are: hep-th
31
The categories of this paper are: ao-sci
5
The categories of this paper are: gr-qc
11
The categories of this paper are: hep-lat
19
The categories of this paper are: eess
24
The categories of this paper are: dg-ga