Search for the lepton-flavor-violating decay KL0 → μe

This thesis presents results on the search for the lepton-flavor-violating decay KL0 → μe. This decay is forbidden in the Standard Model while many alternate models allow it at various rates. These data were collected using a new kaon spectrometer at the Brookhaven National Laboratory Alternating Gradient Synchrotron facility during May, 1987. The sensitivity of the data set is calculated from approximately one million effective KL0 → π+π- decays. Two KL0 → μμ events were identified, a quantity consistent with the known branching ratio for this decay. No candidate KL0 → μe events were detected and a 90% confidence level limit on the branching ratio of B(KL0 → μe) < 0.98 x 10-8 was established. These results represent a significant improvement over the previous limits and serve to constrain some models that allow for lepton flavor violation. The sensitivity of this result probes, through virtual effects, a mass scale on the order of 20 TeV