Non-unitarity of CKM matrix from the vector singlet quark mixing and neutron electric dipole moment

Yi Liao; Xiaoyuan Li

doi:10.1016/s0370-2693(01)00251-9

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arXiv · hep-ph/0005063

Non-unitarity of CKM matrix from the vector singlet quark mixing and neutron electric dipole moment

Yi Liao·Xiaoyuan Li

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Abstract

In the standard model (SM) the lowest order contribution to the quark electric dipole moment (EDM) occurs at the three loop level. We show that the non-unitarity of the CKM matrix in models with an extended quark sector typically gives rise to a quark EDM at the two loop level which has no GIM-like suppression factors except the external quark mass. The induced neutron EDM is of order 10^{-29} e cm and can be well within the reach of the next generation of experiments if it is further enhanced by long distance physics as happens in the SM.

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Yi Liao, Xiaoyuan Li. 2001-01-06. Non-unitarity of CKM matrix from the vector singlet quark mixing and neutron electric dipole moment. https://doi.org/10.1016/s0370-2693(01)00251-9

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