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The Nucleon Anapole Moment and Parity-Violating ep Scattering

Shi-Lin Zhu·S. J. Puglia·B. R. Holstein·M. J. Ramsey-Musolf
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Abstract

Parity-violating (PV) interactions among quarks in the nucleon induce a PV $γNN$ coupling, or anapole moment (AM). We compute electroweak gauge-independent contributions to the AM through ${\cal O}(1/\lamchis)$ in chiral perturbation theory. We estimate short-distance PV effects using resonance saturation. The AM contributions to PV electron-proton scattering slightly enhance the axial vector radiative corrections, R_A^p, over the scale implied by the Standard Model when weak quark-quark interactions are neglected. We estimate the theoretical uncertainty associated with the AM contributions to R_A^p to be large, and discuss the implications for the interpretation PV of ep scattering.

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Shi-Lin Zhu, S. J. Puglia, B. R. Holstein, M. J. Ramsey-Musolf. 2000-04-10. The Nucleon Anapole Moment and Parity-Violating ep Scattering. https://doi.org/10.1103/physrevd.62.033008

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