Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Diffractive production of vector mesons in Deep Inelastic Scattering
  within k_t-factorization approach   In this work we give a theoretical description of the elastic vector meson
production in diffractive DIS developed within the k_t-factorization formalism.
Since the k_t-factorization scheme does not require large values of Q^2+m_V^2,
we conduct an analysis that is applicable to all values of Q^2 from photo- up
to highly virtual production of vector mesons. The basic quantity in this
approach -- the unintegrated gluon structure function -- was for the first time
extracted from the experimental data on F_{2p}, thoroughly investigated, and
consistently used in the vector meson production calculation. Moreover, by
limiting ourselves to the lowest Fock state of the vector meson, we were able
to construct in a closed form the theory of spin-angular coupling in the vector
meson. This allowed us for the first time to address the production of a vector
meson in a given spin-angular state. We performed an extensive analytical and
numerical investigation of the properties of 1S, 2S, and D-wave vector meson
production reactions. Treating the physical ground state vector mesons as
purely 1S states, we observed a good overall agreement with all available
experimental data on vector meson production. For the excited states, our
analysis predicts a picture which is remarkably different from 1S-state, so
that such reactions can be regarded as potential sources of new information on
the structure of excited states in vector mesons.

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The categories of this paper are: math
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The categories of this paper are: bayes-an
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The categories of this paper are: nucl-ex
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The categories of this paper are: hep-lat
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The categories of this paper are: ao-sci
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The categories of this paper are: hep-ex
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The categories of this paper are: quant-ph
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The categories of this paper are: supr-con
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The categories of this paper are: chem-ph
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The categories of this paper are: dg-ga
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The categories of this paper are: gr-qc
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The categories of this paper are: solv-int
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The categories of this paper are: chao-dyn
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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: q-bio