The Dark Side of θ13, δCP, Leptogenesis

In the context of the type-I seesaw mechanism, it is known that θ13 is zero and leptogenesis can not be realized if there exists a flavor symmetry resulting in the Tri-Bimaximal neutrino mixing pattern. We propose a simple framework where additional particles, odd under a Z2 symmetry, break the flavor symmetry and the lightest of the Z2 odd particles is the dark matter candidate. As as result, nonzero θ13, δCP, leptogenesis and the correct dark matter density can be accommodated. On the other hand, a Z2 odd scalar can play the role of the inflaton with mass of 1013 GeV motivated by the recent BICEP2 results. Interestingly, the model can “generate ” δCP ' −pi/2, preferred by the T2K experiment in the normal hierarchy neutrino mass spectrum