Direct CP violation in neutral kaon decays

Abstract

The final result of the NA48 experiment is presented and performed at the CERN SPS neutral kaon beams, on the direct CP violation parameter Re(ε′/ε), as measured from the decay rates of neutral kaons into two pions. The data collected in the years 1997–2001 yield the evidence for the direct CP violation with Re(ε′/ge) = (14.7±2.2) x 10−4. Description of experimental method and systematics, comparison with the corresponding FNAL result and discussion of some implications for the theory are given.