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`Natural Masslessness Conservation' for neutrinos in two Higgs-doublet models

A. Barroso·Joao P. Silva
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Abstract

We present a model which supplements the Standard Electroweak Model with three right-handed neutrinos and one extra scalar doublet which does not develop a vacuum expectation value. With the aid of a discrete symmetry the neutrinos are kept strictly massless. This model has several interesting features. It has unsuppressed lepton flavour violating processes, in particular $μ\rightarrow e γ$, hinting at the possibility that these may soon be within experimental reach. The $Z$ and $W$ interactions become non-diagonal at one loop level. In particular, a non-trivial leptonic mixing matrix is seen to arise from the clash between the charged gauge boson and the charged scalar interactions.

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A. Barroso, Joao P. Silva. 1994-04-10. `Natural Masslessness Conservation' for neutrinos in two Higgs-doublet models. https://doi.org/10.1103/physrevd.50.4581

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