Quark Loop Contribution to Neutron EDM from R-parity Violation

Chiou, Chan-Chi; Kong, Otto C. W.; Vaidya, Rishikesh D.

Quark Loop Contribution to Neutron EDM from R-parity Violation

Authors

Chiou, Chan-Chi

Kong, Otto C. W.

Vaidya, Rishikesh D.

Description

We present a detailed analysis together with numerical calculations on one-loop contributions to the neutron electric dipole moment from supersymmetry without R parity, focusing on the quark-scalar loop contributions. Complete formulas are given for the various contributions through the quark dipole operators. Analytical expressions illustrating the explicit role of the R-parity violating parameters are given following perturbative diagonalization of mass-squared matrices for the scalars. Dominant contributions come from the combinations $B_i^{\ast} λ^{\prime}_{ij1}$ for which we obtain robust bounds. Even if the R-parity violating couplings are real, CKM phase does induce RPV contribution and for some cases such a contribution is as strong as contribution from phases in the R-parity violating couplings. Hence, we have bounds directly on $|B_i^{\ast} ł^{\prime}_{ij1}|$ even if the parameters are all real.
16 pages, 5 figures