Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Photoproduction of J/psi mesons at high energies in parton model and
  k_t-faktorization approach   We consider J/psi meson photoproduction on protons at high energies at the
leading order in alpha_s using conventional parton model and k_t-factorization
approach of QCD. It is shown that in the both cases the colour singlet
mechanism gives correct description for experimental data from HERA for the
total cross section and for the J/psi meson z-spectrum at realistic values of a
c-quark mass and meson wave function at the origin Psi (0). At the same time
our predictions for p_t-spectrum of J/psi meson and for p_t dependence of the
spin parameter alpha obtained in k_t-factorization approach are very different
from the results obtained in conventional parton model. Such a way the
experimental study of a polarized J/psi meson production at the large p_t
should be a direct test of BFKL gluons.

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The categories of this paper are: hep-ex
25
The categories of this paper are: patt-sol
9
The categories of this paper are: nlin
5
The categories of this paper are: gr-qc
19
The categories of this paper are: eess
3
The categories of this paper are: physics
4
The categories of this paper are: cond-mat
7
The categories of this paper are: hep-th
31
The categories of this paper are: ao-sci
35
The categories of this paper are: mtrl-th
33
The categories of this paper are: plasm-ph
32
The categories of this paper are: atom-ph
1
The categories of this paper are: cs
14
The categories of this paper are: math-ph
15
The categories of this paper are: nucl-ex
13
The categories of this paper are: quant-ph