Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: J/psi production in Indium-Indium collisions at 158 GeV/nucleon   The NA60 experiment studies muon pair production at the CERN SPS. In this
letter we report on a precision measurement of J/psi in In-In collisions. We
have studied the J/psi centrality distribution, and we have compared it with
the one expected if absorption in cold nuclear matter were the only active
suppression mechanism. For collisions involving more than ~80 participant
nucleons, we find that an extra suppression is present. This result is in
qualitative agreement with previous Pb-Pb measurements by the NA50 experiment,
but no theoretical explanation is presently able to coherently describe both
results.

7
The categories of this paper are: hep-th
34
The categories of this paper are: chem-ph
28
The categories of this paper are: alg-geom
12
The categories of this paper are: nucl-th
5
The categories of this paper are: gr-qc
4
The categories of this paper are: cond-mat
30
The categories of this paper are: q-alg
16
The categories of this paper are: stat
8
The categories of this paper are: hep-ex
27
The categories of this paper are: comp-gas
10
The categories of this paper are: q-bio
32
The categories of this paper are: atom-ph
26
The categories of this paper are: bayes-an
36
The categories of this paper are: cmp-lg
9
The categories of this paper are: nlin
3
The categories of this paper are: physics