Supersymmetric seesaw model and lepton-flavor violation at a future electron-positron linear collider

Abstract

We study lepton-flavor violating slepton production and decay at a future ${e}^{+}{e}^{\ensuremath{-}}$ linear collider in the context of the seesaw mechanism in minimal supergravity post CERN LEP benchmark scenarios. The present knowledge of the neutrino sector as well as improved future measurements are taken into account. We calculate the signal cross sections $\ensuremath{\sigma}{(e}^{\ifmmode\pm\else\textpm\fi{}}{e}^{\ensuremath{-}}\ensuremath{\rightarrow}{l}_{\ensuremath{\beta}}^{\ifmmode\pm\else\textpm\fi{}}{l}_{\ensuremath{\alpha}}^{\ensuremath{-}}{\stackrel{\ifmmode \tilde{}\else \~{}\fi{}}{\ensuremath{\chi}}}_{b}^{0}{\stackrel{\ifmmode \tilde{}\else \~{}\fi{}}{\ensuremath{\chi}}}_{a}^{0}),$ ${l}_{\ensuremath{\delta}}=e,\ensuremath{\mu},\ensuremath{\tau},$ $\ensuremath{\alpha}\ensuremath{\ne}\ensuremath{\beta},$ and estimate the main background processes. Furthermore, we investigate the correlations of these signals with the corresponding lepton-flavor violating rare decays ${l}_{\ensuremath{\alpha}}\ensuremath{\rightarrow}{l}_{\ensuremath{\beta}}\ensuremath{\gamma}.$ It is shown that these correlations are relatively weakly affected by the uncertainties in the neutrino data but are very sensitive to the model parameters. Hence, they are particularly well suited for probing the origin of lepton-flavor violation.