$\mu\to e \gamma$ Decay in an MSSM Extension

TL;DR

This paper investigates the rare decay $ o e+$ in an extended MSSM model with a vectorlike generation, analyzing loop contributions, CP phases, and experimental constraints to explore the model's parameter space.

Contribution

It provides a detailed one-loop analysis of $ o e+$ decay in an MSSM extension with vectorlike leptons, including CP violation effects and experimental bounds.

Findings

Decay rates are sensitive to new CP phases.

Current MEG limits constrain the extended model parameters.

Future experiments will significantly test the model's viability.

Abstract

An analysis is given of the decay $\mu \to e+ \gamma$ in an MSSM extension with a vectorlike generation. Here mixing with the mirrors allows the possibility of this decay. The analysis is done at the one loop level with the exchange of charginos and neutralinos and of sleptons and mirror sleptons in the loops. A one loop analysis with W and Z boson exchange and mirror leptons and neutrinos is also considered. The effects of CP violating phases from the new sector on the decay $\mu\to e \gamma$ are analyzed in detail. The constraints arising from the current upper limit on the branching ratio ${\cal{B}}(\mu\to {e} \gamma)$ from the MEG experiment of $2.4\times 10^{-12}$ (at 90\% CL) on the parameter space of SUSY models and on vectorlike models are explored. Further, the MEG experiment is likely to improve the upper limit by an order of magnitude in the coming years. The improved limits will allow one to probe a much larger domain of the parameter space of the extended models.