EPS HEP 2015

A minimal seesaw model with the mu-tau symmetry

Not scheduled

15m

poster Neutrino Physics

Speaker

Darius Jurciukonis (Vilnius University (LT))

Description

Assuming a minimal seesaw model with two right-handed singlet Majorana neutrinos we analyse light neutrino masses and oscillation angles induced by the $\mu$-$\tau$ symmetry. A general neutrino mass matrix, that is invariant with respect to the $\mu$-$\tau$ symmetry, gives $\theta_{23}=45$ degree and $\theta_{13}=0$. Applying radiative corrections we break this flavor symmetry and reproduce the observed neutrino oscillation phenomenology. The Higgs sector of our model is constructed with two Higgs doublets and a CP-invariant Higgs potential which allows to establish the conditions for the Higgs mixing angles. We assume an auxiliary symmetry $Z_2$ for the Higgs sector. The second Higgs doublet breaks the $\mu$-$\tau$ symmetry spontaneously. We analyse the light neutrino masses numerically as functions of the heavy neutrino masses. Both normal and inverted hierarchies of the light neutrino masses are discussed. We choose values for the parameters of the model at tree-level by numerical scans, where we look for the best agreement between the computed and experimental neutrino oscillation angles. In addition, the influence of different Yukawa coupling strengths to the Higgs mass distributions and the neutrino oscillation phenomenology is analysed.