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$epsilon/epsilon$ Anomaly and Neutron EDM in $SU(2)_Ltimes SU(2)_Rtimes U(1)_{B-L}$ model with Charge Symmetry

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 نشر من قبل Toshifumi Yamada
 تاريخ النشر 2018
  مجال البحث
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The Standard Model prediction for $epsilon/epsilon$ based on recent lattice QCD results exhibits a tension with the experimental data. We solve this tension through $W_R^+$ gauge boson exchange in the $SU(2)_Ltimes SU(2)_Rtimes U(1)_{B-L}$ model with `charge symmetry, whose theoretical motivation is to attribute the chiral structure of the Standard Model to the spontaneous breaking of $SU(2)_Rtimes U(1)_{B-L}$ gauge group and charge symmetry. We show that $M_{W_R}<58$ TeV is required to account for the $epsilon/epsilon$ anomaly in this model. Next, we make a prediction for the neutron EDM in the same model and study a correlation between $epsilon/epsilon$ and the neutron EDM. We confirm that the model can solve the $epsilon/epsilon$ anomaly without conflicting the current bound on the neutron EDM, and further reveal that almost all parameter regions in which the $epsilon/epsilon$ anomaly is explained will be covered by future neutron EDM searches, which leads us to anticipate the discovery of the neutron EDM.

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