Neutrino Mixing and the Pattern of Supersymmetry Breaking

TL;DR

This paper investigates how large mu-tau neutrino mixing affects lepton flavor violation in supersymmetric models, highlighting potential conflicts with experimental limits depending on the model specifics.

Contribution

It provides a detailed calculation of lepton flavor violating transition rates considering large neutrino mixing angles within supersymmetric frameworks.

Findings

Branching ratio for mu to e gamma often exceeds experimental limits in modular invariant models.

Predicted rates in radiatively induced mixing models can reach current experimental bounds with large Yukawa couplings.

Uncertainty analysis clarifies the robustness of the predicted lepton flavor violation rates.

Abstract

We study the implications of a large $\nu_\mu - \nu_\tau$ mixing angle on lepton flavour violating radiative transitions in supersymmetric extensions of the standard model. The transition rates are calculated to leading order in $\epsilon$, the parameter which characterizes the flavour mixing. The uncertainty of the predicted rates is discussed in detail. For models with modular invariance the branching ratio $BR(\mu \to e \gamma)$ mostly exceeds the experimental upper limit. In models with radiatively induced flavour mixing the predicted range includes the upper limit, if the Yukawa couplings in the lepton sector are large, as favoured by Yukawa coupling unification.