Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Parameterization of the quark-quark correlator of a spin-1/2 hadron   The general parameterization of the quark-quark correlation function for a
spin-1/2 hadron is considered. The presence of the Wilson line ensuring color
gauge invariance of the correlator induces structures that were not given
explicitly in the existing literature. In particular, the general form of the
transverse momentum dependent correlator entering various hard scattering
processes is derived. In this case two new time-reversal odd parton
distributions appear at the twist-3 level.

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The categories of this paper are: atom-ph
4
The categories of this paper are: cond-mat
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The categories of this paper are: eess
20
The categories of this paper are: acc-phys
37
The categories of this paper are: supr-con
24
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: funct-an
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The categories of this paper are: quant-ph
6
The categories of this paper are: astro-ph
18
The categories of this paper are: econ
34
The categories of this paper are: chem-ph
5
The categories of this paper are: gr-qc
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The categories of this paper are: hep-th
25
The categories of this paper are: patt-sol
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The categories of this paper are: mtrl-th