Search for lepton flavor violation with muons

Now that the neutrino oscillation phenomena have been established, any new physics scenario beyond the standard model necessarily involves lepton flavor violation (LFV) also in the charged lepton sector. Particularly TeV supersymmetry predicts large branching ratios for some of the LFV processes that may be accessible to coming experiments. Most promising LFV processes are the rare muon decays μ → eγ and μ → e conversion, which require quite different experimental approaches. The first of such LFV search experiments that are sensitive to new physics, is the MEG experiment. It aims to discover μ → eγ with at least two orders of magnitude higher sensitivity than previous experiments. It might lead to first clear evidence of new physics, likely to be supersymmetry, just before LHC start-up. Experiments looking for μ → e conversion, MECO, and PRISM/PRIME later, are also being prepared. (author)