Gauged B-x_i L origin of R parity and its implications

TL;DR

This paper proposes a modified gauged B-L symmetry, called B-x_i L, which naturally forbids dangerous proton decay operators while providing a gauge origin for R parity in supersymmetric models.

Contribution

It introduces two minimal models with B-x_i L symmetry that successfully prevent proton decay operators and generate realistic neutrino masses.

Findings

B-x_i L symmetry forbids dimension-five proton decay operators.

The models accommodate realistic neutrino mass matrices.

Implications for supersymmetric phenomenology are discussed.

Abstract

Gauged B-L is a popular candidate for the origin of the conservation of R parity, i.e. R = (-)^{3B+L+2j}, in supersymmetry, but it fails to forbid the effective dimension-five terms arising from the superfield combinations QQQL, uude, and uddN, which allow the proton to decay. Changing it to B-x_i L, where x_e+x_\mu+x_\tau=3 (with x_i not equal to 1) for the three families, would forbid these terms while still serving as a gauge origin of R parity. We show how this is achieved in two minimal models with realistic neutrino mass matrices, and discuss their phenomenological implications.