Lepton electric dipole moment and strong CP violation
Abstract
Contribution of the strong CP angle, θ bar , to the Wilson Coefficients of electron and muon electric dipole moment (EDM) operators are discussed. Previously, θ bar contribution to the electron EDM operator was calculated by Choi and Hong [1]. However, the effect of CP-violating three meson coupling was missing in [1]. We include this missing contribution for the first time in the literature, and reevaluate the Wilson coefficients of the lepton EDM operator. We obtain de = - (2.2 - 8.6) ×10-28 θ bar e-cm which is 15-70% of the result obtained in [1]. We also estimated the muon EDM as dμ = - (0.5 - 1.8) ×10-25 θ bar e-cm. Using | θ bar | ≲10-10 suggested by the neutron EDM measurements, we obtain |de | ≲ 8.6 ×10-38e-cm and |dμ | ≲ 1.8 ×10-35e-cm. The θ bar contribution to the muon EDM is much below the sensitivities of the current and near future experiments. Our result shows that the θ bar contribution to de,μ can be larger than the CKM contributions by many orders of magnitude.
- Publication:
-
Physics Letters B
- Pub Date:
- February 2018
- DOI:
- 10.1016/j.physletb.2017.12.052
- arXiv:
- arXiv:1709.05866
- Bibcode:
- 2018PhLB..777..335G
- Keywords:
-
- High Energy Physics - Phenomenology;
- High Energy Physics - Experiment
- E-Print:
- 10 pages, 2 figures