Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Low Mass Dimuon Production in Indium-Indium Collisions at the CERN SPS   NA60 is a fixed-target experiment at the CERN SPS which measured dimuon
production in nucleus-nucleus and proton-nucleus collisions. In this paper we
report on a precision measurement of low-mass muon pairs in 158 AGeV
indium-indium collisions. A significant excess of pairs is observed above the
yield expected from neutral meson decays. The excess can be isolated by
subtraction of expected sources, thanks to the excellent mass resolution and
large sample size.

8
The categories of this paper are: hep-ex
10
The categories of this paper are: q-bio
5
The categories of this paper are: gr-qc
23
The categories of this paper are: solv-int
37
The categories of this paper are: supr-con
24
The categories of this paper are: dg-ga
29
The categories of this paper are: funct-an
12
The categories of this paper are: nucl-th
32
The categories of this paper are: atom-ph
7
The categories of this paper are: hep-th
36
The categories of this paper are: cmp-lg
26
The categories of this paper are: bayes-an
21
The categories of this paper are: adap-org
20
The categories of this paper are: acc-phys
14
The categories of this paper are: math-ph
30
The categories of this paper are: q-alg