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The electric dipole form factor of the nucleon

W. H. Hockings·U. van Kolck
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Abstract

The electric dipole form factor of the nucleon stemming from the QCD $\barθ$ term is calculated in chiral perturbation theory in leading order. To this order, the form factor originates from the pion cloud. Its momentum-dependence is proportional to a non-derivative time-reversal-violating pion-nucleon coupling, and the scale for momentum variation--appearing, in particular, in the radius of the form factor--is the pion mass.

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W. H. Hockings, U. van Kolck. 2005-08-04. The electric dipole form factor of the nucleon. https://doi.org/10.1016/j.physletb.2004.11.043

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