Enhanced Higgs mediated lepton flavour violating processes in the supersymmetric inverse seesaw model

Asmaa Abada,Cédric Weiland,Debottam Das

doi:10.1007/jhep03(2012)100

Abstract

Abstract We study the impact of the inverse seesaw mechanism on several low-energy flavour violating observables such as τ → μμμ in the context of the Minimal Supersymmetric Standard Model. As a consequence of the inverse seesaw, the contributions of the right-handed sneutrinos significantly enhance the Higgs-mediated penguin diagrams. We find that different flavour violating branching ratios can be enhanced by as much as two orders of magnitude. We also comment on the impact of the Higgs-mediated processes on the leptonic B-meson decays and on the Higgs flavour violating decays.

Highlights

JHEP03(2012)100 that such models might give rise to cLFV
We study the impact of the inverse seesaw mechanism on several low-energy flavour violating observables such as τ → μμμ in the context of the Minimal Supersymmetric Standard Model
When compared to other SUSY seesaw realisations, cLFV observables are enhanced in this framework, and such an enhancement can be attributed to large neutrino Yukawa couplings (Yν ∼ O(1)), compatible with a seesaw scale M, close to the electroweak one, within LHC reach

Summary

Inverse seesaw mechanism in the MSSM

MRi represents the right-handed neutrino mass term which conserves lepton number. A generic superpotential with (−1)L should contain the latter term, let us notice that similar to what occurs for μXi, the absence of μνic enhances the symmetry of the model; we emphasise that it is the magnitude of μXi (and not that of μνic) which controls the size of the light neutrino mass [36, 41]. In order to illustrate the pattern of light neutrino masses in the inverse seesaw model and how it is related to the lepton number violating parameter μXi, we consider the onegeneration case. Assuming MR ∼ O(TeV), the effective mass term will not be very large, in clear contrast to what occurs in the standard (type I) SUSY seesaw. We will be interested in the role of such a light sneutrino (i.e. Mν2c ∼ MS2USY) in the enhancement of Higgs mediated contributions to lepton flavour violating observables

Lepton flavour violation

Higgs-mediated lepton flavour violating observables

Results and discussion

Conclusions