Non-zero U_{e3} and TeV-Leptogenesis through A_4 symmetry breaking

Understand

We consider an effective theory with an $SU(2)\times U(1)\times A_{4}\times Z_{2}\times Z_{4}$ symmetry and investigate the possibility of a linking TeV-leptogenesis with a reactor angle $|U_{e3}|$ through spontaneous $A_{4}$ symmetry breaking which is at a scale higher than electroweak scale under the framework of radiative seesaw.

• It has been shown that tri-bimaximal(TBM) can be obtained by forging vacuum expectation value (VEV) alignment of the $A_{4}$.
• Especially, one $A_{4}$ triplet scalar field with cut-off scale $\Lambda$ is added in neutrino Yukawa sector, which is responsible for the deviation of the exact TBM, to explain leptogenesis as well as a non-zero $|U_{e3}|$.
• Above the scale of $\Lambda$ the leptonic Yukawa sectors will lead to the exact TBM.