Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Diffractive Photoproduction of $\Upsilon$ at HERA   Predictions for the diffractive photoproduction of the $\Upsilon$-family at
HERA energies, within the framework of the analysis by Frankfurt, Koepf and
Strikman, are presented. Two novel effects lead to a significant enhancement of
the original calculation: the non-diagonal (or skewed) kinematics, calculated
to leading-log($Q^2$) accuracy, and the large magnitude of the real part of the
amplitude. The resultant cross sections are found to agree fairly well with
recent preliminary data from ZEUS and H1. A strong correlation between the mass
of the diffractively produced state and the energy dependence of the cross
section is found. In particular, a considerably stronger rise in energy is
predicted than that found in $J/\psi$-production.

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The categories of this paper are: q-fin
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The categories of this paper are: hep-th
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The categories of this paper are: acc-phys
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The categories of this paper are: chao-dyn
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The categories of this paper are: patt-sol
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The categories of this paper are: econ
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The categories of this paper are: solv-int
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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: nucl-ex
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The categories of this paper are: eess
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The categories of this paper are: hep-lat
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The categories of this paper are: nlin
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The categories of this paper are: mtrl-th
10
The categories of this paper are: q-bio
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The categories of this paper are: math-ph