Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Spin effects in the fragmentation of a transversely polarized quark   An azimuthal dependence of pions produced in polarized Deep Inelastic
Scattering, gamma^* - p(transv. polarized) -> pion + X, has been recently
observed and might be related to the so-called Collins effect. We discuss in
details, for a general spin configuration of the nucleon, the kinematics of the
process and methods of extracting information on the fragmentation properties
of a polarized quark. Assuming that the observed azimuthal dependence is indeed
due to Collins effect, we derive a lower bound estimate for the size of the
quark analysing power, which turns out to be large.

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The categories of this paper are: nucl-ex
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The categories of this paper are: cmp-lg
32
The categories of this paper are: atom-ph
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The categories of this paper are: econ
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The categories of this paper are: q-fin
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The categories of this paper are: adap-org
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The categories of this paper are: astro-ph
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The categories of this paper are: hep-lat
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The categories of this paper are: hep-th
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The categories of this paper are: bayes-an
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The categories of this paper are: ao-sci
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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: alg-geom
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The categories of this paper are: cond-mat
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The categories of this paper are: physics