Measurement of direct CP violation with the experiment NA48 at CERN

TL;DR

This paper reports the measurement of direct CP violation in neutral kaon decays, specifically quantifying Re(epsilon'/epsilon) using data from CERN's NA48 experiment, providing evidence for CP violation beyond indirect effects.

Contribution

It presents the first measurement of Re(epsilon'/epsilon) in neutral kaon decays at CERN's NA48, demonstrating direct CP violation.

Findings

Re(epsilon'/epsilon) = (18.5 +/- 4.5 (stat) +/- 5.8 (syst)) x 10^(-4)

Evidence of direct CP violation in neutral kaon decays

Quantitative analysis of CP violation parameters

Abstract

Direct CP violation is studied in two pion decays of the neutral kaon. Using data collected in the first beam period in 1997, the result for the parameter Re(epsilon'/epsilon) is (18.5+/-4.5(stat)+/-5.8(syst))x10^(-4).