Charged Lepton Flavor Violation in the Semi-Constrained NMSSM with Right-Handed Neutrinos

TL;DR

This paper investigates the bc e0 e ade4 decay in a semi-constrained NMSSM with right-handed neutrinos, showing potential observability at TeV-scale SUSY with implications for flavor violation.

Contribution

It introduces a semi-constrained boundary condition framework in the NMSSM with right-handed neutrinos, analyzing lepton flavor violation and its experimental prospects.

Findings

bc e0 e ade4 decay rates can be sizable and observable.

Parameter space consistent with Higgs mass allows detectable bc e0 e ade4 decay.

SUSY mass scale around 4 TeV still permits observable lepton flavor violation.

Abstract

We study the \mu \to e \gamma decay in the Z_3-invariant next-to-minimal supersymmetric (SUSY) Standard Model (NMSSM) with superheavy right-handed neutrinos. We assume that the soft SUSY breaking parameters are generated at the GUT scale, not universally as in the minimal supergravity scenario but in such a way that those soft parameters which are specific to the NMSSM can differ from the soft parameters which involve only the MSSM fields while keeping the universality at the GUT scale within the soft parameters for the MSSM and right-handed neutrino fields. We call this type of boundary conditions "semi-constrained". In this model, the lepton-flavor-violating off-diagonal elements of the slepton mass matrix are induced by radiative corrections from the neutrino Yukawa couplings, just like as in the MSSM extended with the right-handed neutrinos, and these off-diagonal elements induce sizable rates of \mu \to e \gamma depending on the parameter space. Since this model has more free parameters than the MSSM, the parameter region favored from the Higgs boson mass can slightly differ from that in the MSSM. We show that there is a parameter region in which the \mu \to e \gamma decay can be observable in the near future even if the SUSY mass scale is about 4 TeV.