Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Measurement of the ttbar production cross section using dilepton events
  in ppbar collisions   We present a measurement of the ttbar production cross section sigma(ttbar)
in ppbar collisions at sqrt{s} = 1.96 TeV using 5.4 fb-1 of integrated
luminosity collected with the D0 detector. We consider final states with at
least two jets and two leptons (ee, emu, mumu), and events with one jet for the
the emu final state as well. The measured cross section is sigma(ttbar)= 7.36
+0.90-0.79 (stat + syst) pb. This result combined with the cross section
measurement in the lepton + jets final state yields sigma(ttbar)=7.56
+0.63-0.56 (stat + syst) pb, which agrees with the standard model expectation.
The relative precision of 8% of this measurement is comparable to the latest
theoretical calculations.

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The categories of this paper are: comp-gas
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The categories of this paper are: nucl-ex
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The categories of this paper are: math
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The categories of this paper are: acc-phys
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The categories of this paper are: cond-mat
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The categories of this paper are: astro-ph
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The categories of this paper are: q-alg
1
The categories of this paper are: cs
5
The categories of this paper are: gr-qc
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The categories of this paper are: supr-con
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The categories of this paper are: hep-lat
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The categories of this paper are: mtrl-th
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The categories of this paper are: alg-geom
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The categories of this paper are: plasm-ph
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The categories of this paper are: eess
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The categories of this paper are: econ