Neutrino Masses in Supersymmetry: R-Parity and Leptogenesis

TL;DR

This paper discusses how supersymmetric models can generate neutrino masses while maintaining successful leptogenesis, highlighting the implications of R-parity conservation and the potential for observable new particles.

Contribution

It demonstrates that neutrino masses and leptogenesis can coexist in supersymmetry with R-parity conservation, addressing issues related to lepton asymmetry erasure.

Findings

R-parity violation erases lepton asymmetry before electroweak transition

Neutrino masses can be generated with R-parity conservation

Predictions include possible new observable particles

Abstract

In the supersymmetric standard model of particle interactions, R-parity nonconservation is often invoked to obtain nonzero neutrino masses. We point out here that such interactions of the supersymmetric particles would erase any pre-existing lepton or baryon asymmetry of the universe before the electroweak phase transition through the $B + L$ violating sphaleron processes. We then show how neutrino masses may be obtained in supersymmetry (assuming R-parity conservation) together with successful leptogenesis and predict the possible existence of new observable particles.