Mass Spectrum Dependence of Higgs-mediated mu-e Transition in the MSSM

TL;DR

This study explores how Higgs-mediated mu-e transition effects in the MSSM depend on the mass spectrum, especially in non-universal Higgs mass models with heavy SUSY particles, revealing significant sensitivity to mass parameters and flavor violation chirality.

Contribution

It provides a detailed analysis of the mass spectrum dependence of Higgs-mediated mu-e transitions in the MSSM, considering non-universal Higgs masses and flavor mixing, highlighting the impact of split mass scales and interference effects.

Findings

The ratio BR(μ→eγ)/BR(μ→3e) is highly sensitive to SUSY mass parameters.

The mass spectrum structure and flavor violation chirality drastically influence the transition ratio.

Logarithmic factors from split mass scales significantly affect interference between contributions.

Abstract

In this paper, we study non-decoupling $\mu$ - $e$ transition effects by Higgs-mediated contribution in the MSSM, when some SUSY mass parameters are much greater than TeV. In order to treat CP-odd Higgs mass $m_{A^{0}}$ as a free parameter, we consider the non-universal Higgs mass model (NUHM), and assume the only left- or right-handed sleptons had flavor-mixing mass terms. If both Higgs-mediated and ordinary SUSY contribution are significant, the ratio of branching ratios $\BR(\meg) / \BR(\maleal)$ becomes sensitive to SUSY mass parameters. We investigated these mass-sensitive regions and the behavior of the ratio $\BR(\meg) / \BR(\maleal)$ in some mass spectrum of the NUHM, and found that this ratio drastically depends on the mass spectrum structure and chirality of flavor violation. Log factor from two split mass scale influences the way of interference between gaugino- and Higgs-mediated contributions significantly.