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arXiv · 1010.4078

The Electric Dipole Form Factor of the Nucleon in Chiral Perturbation Theory to Sub-leading Order

E. Mereghetti·J. de Vries·W. H. Hockings·C. M. Maekawa·U. van Kolck
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Abstract

The electric dipole form factor (EDFF) of the nucleon stemming from the QCD theta term and from the quark color-electric dipole moments is calculated in chiral perturbation theory to sub-leading order. This is the lowest order in which the isoscalar EDFF receives a calculable, non-analytic contribution from the pion cloud. In the case of the theta term, the expected lower bound on the deuteron electric dipole moment is |d_d| > 1.4 10^(-4) \theta e fm. The momentum dependence of the isovector EDFF 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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E. Mereghetti, J. de Vries, W. H. Hockings, C. M. Maekawa, U. van Kolck. 2010-10-20. The Electric Dipole Form Factor of the Nucleon in Chiral Perturbation Theory to Sub-leading Order. https://doi.org/10.1016/j.physletb.2010.12.018

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