Results on Rare Kaon Decays from the NA48 Experiment

the understanding of CP violation in kaon decays. A relatively large eect of indirect CP violation is observed in the KL ! e mode, and constraints can be put on the very rare e decay, that is expected to manifest direct CP violation. The other strong motivation for these studies is the understanding of low{energy hadron dynamics, by probing non{perturbative eective theories such as Chiral Perturbation Theory (PT). Cagliari, Cambridge, CERN, Dubna, Edinburgh, Ferrara,Firenze, Mainz, Orsay, Perugia, Pisa, Saclay, Siegen, Torino, Warsaw, Wien Decay B.R. (order) Main motivations indirect CPV 10 test of PT at O(p ), constraints on (KL ! e e KL ! e e 10 main background to KL ! check of KL ! e analysis e < 10 constraints on (KL ! KS ! 10 clean PT prediction < 10 indirect CPV, test of CPT ! e e 10 ! p < 10 S = 2 transition Table 1: A non-ex