Lepton number violation in decays of supersymmetric particles

We discuss lepton flavour violating signals at the LHC in the framework of supersymmetric theories. We consider R-parity conserving as well as R-parity violating scenarios. In the case of R-parity conservation we show that in decays of supersymmetric particles large parameter regions exist where lepton flavour violating decay modes have large branching ratios despite the stringent constraints from the non-observation of rare lepton decays. We discuss briefly some consequences for discovery potential and the measurements of edge-variables at LHC within the SPS1a scenario. In the case of R-parity violating scenarios we focus on bilinear R-parity violation. We discuss correlations between the decays of the lightest neutralino and neutrino mixing angles as well as the possibilities to measure these correlations at LHC.