Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Measurement of the ttbar production cross section in ppbar collisions
  using dilepton events   We present a measurement of the ttbar pair production cross section in ppbar
collisions at sqrt(s) = 1.96 TeV utilizing approximately 425 pb-1 of data
collected with the D0 detector. We consider decay channels containing two high
pT charged leptons (either e or \mu) from leptonic decays of both top-daughter
W bosons. These were gathered using four sets of selection criteria, three of
which required that a pair of fully identified leptons (i.e., e\mu, ee, or
\mu\mu) be found. The fourth approach imposed less restrictive criteria on one
of the lepton candidates and required that at least one hadronic jet in each
event be tagged as containing a b quark. For a top quark mass of 175 GeV, the
measured cross section is 7.4 +/-1.4(stat} +/- 1.0(syst) pb.

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The categories of this paper are: nlin
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The categories of this paper are: nucl-ex
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The categories of this paper are: chem-ph
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The categories of this paper are: patt-sol
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The categories of this paper are: adap-org
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The categories of this paper are: math
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The categories of this paper are: q-fin
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The categories of this paper are: hep-lat
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The categories of this paper are: dg-ga
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The categories of this paper are: q-alg
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The categories of this paper are: funct-an
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The categories of this paper are: comp-gas
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The categories of this paper are: cond-mat
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The categories of this paper are: mtrl-th
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The categories of this paper are: hep-th
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The categories of this paper are: physics