Neutron EDM in Four Generation Standard Model
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.
Cite
@article{arxiv.1107.3642,
title = {Neutron EDM in Four Generation Standard Model},
author = {Junji Hisano and Wei-Shu Hou and Fanrong Xu},
journal= {arXiv preprint arXiv:1107.3642},
year = {2013}
}
Comments
4 pages; 5 pages, references added, comment added on hyperon EDM, note added on on t' mass and Higgs mass after EPS-HEP 2011