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P- and T-violating $πN N$ form factor

S. Kondratyuk·P. G. Blunden
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Abstract

The form factor of the parity and time-reversal violating (PTV) pion-nucleon interaction is calculated from one-loop vertex diagrams. The degrees of freedom included in the effective lagrangian are nucleons, pions, $η$, $ρ$ and $ω$ mesons. We show that by studying the form factor one can constrain the PTV meson-nucleon coupling constants. We evaluate the mean square radius associated with the PTV $πN N$ vertex. Using the mean square radius, we estimate the effect of the PTV $πN N$ vertex on the neutron electric dipole moment, and find a very small correction. We also extract the renormalisation group $β$ function and use it to discuss evolution of the PTV $πN N$ coupling constant beyond the hadronic mass scale.

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S. Kondratyuk, P. G. Blunden. 2006-12-16. P- and T-violating $πN N$ form factor. https://doi.org/10.1016/j.nuclphysa.2006.12.054

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