CP phases in the charged current and Higgs sectors for Majorana neutrinos

Abstract

The diagonalization of the leptonic mass matrices is performed in the framework of the triplet model to generate Majorana mass terms for neutrinos. This allows the understanding of the role played by the CP-violating phases in the Higgs sector and their relation with those of the charged-current Lagrangian. It is shown that all the leptonic mixings, including those of the Higgs couplings, can be given in terms of a Kobayashi-Maskawa matrix and the relative Majorana phases of the neutrino fields. The characteristic Majorana phases, always appearing together with the neutrino mass, are present in |∆L|=2 pieces and they show up in processes with a) neutrino-antineutrino propagation, and/or b) at least two different neutrinos as asymptotic states, and/or c) a vertex with a doubly-charged scalar. The phenomenological implications for processes with these characteristics are given.