Enhanced μ−-e− conversion in nuclei in the inverse seesaw model

We investigate nuclear μ−-e− conversion in the framework of an effective Lagrangian arising from the inverse seesaw model of neutrino masses. We consider lepton flavour violation interactions that arise from short range (non-photonic) as well as long range (photonic) contributions. Upper bounds for the L̸f-parameters characterizing μ−-e− conversion are derived in the inverse seesaw model Lagrangian using the available limits on the μ−-e− conversion branching ratio, as well as the expected sensitivities of upcoming experiments. We comment on the relative importance of these two types of contributions and their relationship with the measured solar neutrino mixing angle θ12 and the dependence on θ13. Finally we show how the L̸f μ−-e− conversion and the μ−→e−γ rates are strongly correlated in this model.