Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Differential cross sections and spin density matrix elements for the
  reaction gamma p -> p omega   High-statistics differential cross sections and spin density matrix elements
for the reaction gamma p -> p omega have been measured using the CLAS at
Jefferson Lab for center-of-mass (CM) energies from threshold up to 2.84 GeV.
Results are reported in 112 10-MeV wide CM energy bins, each subdivided into
cos(theta_CM) bins of width 0.1. These are the most precise and extensive omega
photoproduction measurements to date. A number of prominent structures are
clearly present in the data. Many of these have not previously been observed
due to limited statistics in earlier measurements.

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The categories of this paper are: supr-con
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The categories of this paper are: stat
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The categories of this paper are: econ
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The categories of this paper are: funct-an
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The categories of this paper are: gr-qc
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The categories of this paper are: atom-ph
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The categories of this paper are: physics
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The categories of this paper are: hep-ex
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The categories of this paper are: solv-int
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The categories of this paper are: plasm-ph
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The categories of this paper are: mtrl-th
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The categories of this paper are: adap-org
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The categories of this paper are: patt-sol
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The categories of this paper are: comp-gas
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The categories of this paper are: chem-ph
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The categories of this paper are: bayes-an