Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Exclusive photoproduction of {\bf $\Upsilon$} mesons at HERA   The exclusive photoproduction reaction gamma p --> Upsilon p has been studied
with the ZEUS experiment in ep collisions at HERA using an integrated
luminosity of 468 pb^{-1}. The measurement covers the kinematic range 60<W<220
GeV and Q^2<1 GeV^2, where W is the photon-proton centre-of-mass energy and Q^2
is the photon virtuality. These results, which represent the analysis of the
full ZEUS data sample for this channel, are compared to predictions based on
perturbative QCD.

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The categories of this paper are: eess
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The categories of this paper are: econ
5
The categories of this paper are: gr-qc
0
The categories of this paper are: hep-ph
26
The categories of this paper are: bayes-an
27
The categories of this paper are: comp-gas
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The categories of this paper are: hep-lat
37
The categories of this paper are: supr-con
35
The categories of this paper are: mtrl-th
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The categories of this paper are: stat
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The categories of this paper are: math-ph
31
The categories of this paper are: ao-sci
28
The categories of this paper are: alg-geom
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The categories of this paper are: nlin
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The categories of this paper are: funct-an
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The categories of this paper are: physics