Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Strong CP violation and the neutron electric dipole form factor   We calculate the neutron electric dipole form factor induced by the CP
violating theta-term of QCD, within a perturbative chiral quark model which
includes pion and kaon clouds. On this basis we derive the neutron electric
dipole moment and the electron-neutron Schiff moment. From the existing
experimental upper limits on the neutron electric dipole moment we extract
constraints on the theta-parameter and compare our results with other
approaches.

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The categories of this paper are: astro-ph
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The categories of this paper are: math
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The categories of this paper are: cond-mat
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The categories of this paper are: ao-sci
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The categories of this paper are: chao-dyn
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The categories of this paper are: q-fin
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The categories of this paper are: quant-ph
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The categories of this paper are: acc-phys
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The categories of this paper are: bayes-an
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The categories of this paper are: stat
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The categories of this paper are: alg-geom
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The categories of this paper are: eess
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The categories of this paper are: atom-ph
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The categories of this paper are: math-ph
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The categories of this paper are: nucl-ex
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The categories of this paper are: chem-ph