Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Charge symmetry violation in the parton distributions of the nucleon   We point out that charge symmetry violation in both the valence and sea quark
distributions of the nucleon has a non-perturbative source. We calculate this
non-perturbative charge symmetry violation using the meson cloud model, which
has earlier been successfully applied to both the study of SU(2) flavour
asymmetry in the nucleon sea and quark-antiquark asymmetry in the nucleon. We
find that the charge symmetry violation in the valence quark distribution is
well below 1%, which is consistent with most low energy tests but significantly
smaller than the quark model prediction about 5%-10%. Our prediction for the
charge symmetry violation in the sea quark distribution is also much smaller
than the quark model calculation.

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The categories of this paper are: stat
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The categories of this paper are: eess
26
The categories of this paper are: bayes-an
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The categories of this paper are: dg-ga
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The categories of this paper are: adap-org
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The categories of this paper are: hep-ex
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The categories of this paper are: alg-geom
5
The categories of this paper are: gr-qc
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The categories of this paper are: atom-ph
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The categories of this paper are: cond-mat
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The categories of this paper are: supr-con
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The categories of this paper are: acc-phys
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The categories of this paper are: cs
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The categories of this paper are: astro-ph
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The categories of this paper are: solv-int
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The categories of this paper are: nlin