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arXiv · hep-ph/0007266

Bilinear R-parity Violation and Small Neutrino Masses: a Self-consistent Framework

J. M. Mira·E. Nardi·D. A. Restrepo·J. W. F. Valle
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Abstract

We study extensions of supersymmetric models without R-parity which include an anomalous U(1)_H horizontal symmetry. Bilinear R-parity violating terms induce a neutrino mass at tree level of approximately $(θ^2)^δ$ eV where $θ\approx 0.22$ is the U(1)_H breaking parameter and $δ$ is an integer number that depends on the horizontal charges of the leptons. For $δ=1$ a unique self-consistent model arises in which i) all the superpotential trilinear R-parity violating couplings are forbidden by holomorphy; ii) the tree level neutrino mass falls in the range suggested by the atmospheric neutrino problem; iii) radiative contributions to neutrino masses are strongly suppressed resulting in a squared solar mass difference of few 10^{-8} eV^2 which only allows for the LOW (or quasi-vacuum) solution to the solar neutrino problem; iv) the neutrino mixing angles are not suppressed by powers of $θ$ and can naturally be large.

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J. M. Mira, E. Nardi, D. A. Restrepo, J. W. F. Valle. 2000-07-29. Bilinear R-parity Violation and Small Neutrino Masses: a Self-consistent Framework. https://doi.org/10.1016/s0370-2693(00)01067-4

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