A Minimal Model of Neutrino Flavor

by Krishna Mohan Parattu (IUCAA, Pune, India)

Friday 9 Nov 2012, 11:00 → 12:00 Europe/Paris

Room 149, Batiment 1 (LPSC)

Previously, in a paper titled "Tribimaximal mixing from small groups" (arxiv:hep-ph/1012.2842v2), we had conducted a systematic scan of the application of discrete groups to neutrino mixing. Under some very reasonable assumptions, we observed that the Frobenius group T7, a group of 21 elements, was the smallest discrete group which produced tribimaximal mixing (TBM) at leading order ( theta12 = 35:3 , theta 23 = 45 , theta 13 = 0 ). In this talk, I will present recent work where we have built upon this insight and constructed an explicit model based on T7 with only two flavon fields. At leading order, our model produces TBM as well as the experimentally observed value of approximately 30 for the ratio of m3^2 - m1^2 to m2^2 - m1^2 in the neutrino sector. We next consider the Next-to-Leading Order (NLO) terms allowed by the symmetry and identify the terms that can raise the value of the reactor angle theta13 so that it becomes compatible with the recent results of Daya Bay and Reno reactors ( theta13~9 degrees ), without compromising the agreement of the other angles with experiment. An ultraviolet completion of the model that will restrict the NLO terms to just these terms is indicated. Finally, we show how the required flavon alignments can be achieved by introducing a set of "hidden" scalars which are assigned charges such that they couple only to the flavons and not to the leptons.