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arXiv · 1107.3642

Neutron EDM in Four Generation Standard Model

Junji Hisano·Wei-Shu Hou·Fanrong Xu
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Abstract

A fourth generation of quarks, if it exist, may provide sufficient CP violation for the baryon asymmetry of the Universe. We estimate the neutron electric dipole moment in the presence of a fourth generation, and find it would be dominated by the strange quark chromoelectric dipole moment, assuming it does not get wiped out by a Peccei-Quinn symmetry. Both the three electroweak loop and the two-loop electroweak/one-loop gluonic contributions are considered. With m_{b'}, m_{t'} at 500 GeV or so that can be covered at the LHC, and with a Jarlskog CPV factor that is consistent with hints of New Physics in b to s transitions, the neutron EDM is found around 10^{-31}e cm, still far below the 10^{-28}e cm reach of the new experiments being planned or under construction.

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Junji Hisano, Wei-Shu Hou, Fanrong Xu. 2011-07-31. Neutron EDM in Four Generation Standard Model. https://doi.org/10.1103/physrevd.84.093005

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