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A new measurement of direct CP violation in two pion decays of the neutral kaon

The NA48 Collaboration·V. Fanti
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Abstract

The NA48 experiment at CERN has performed a new measurement of direct CP violation, based on data taken in 1997 by simultaneously collecting K_L and K_S decays into pi0pi0 and pi+pi-. The result for the CP violating parameter Re(epsilon'/epsilon) is (18.5 +/- 4.5(stat)} +/- 5.8 (syst))x10^{-4}.

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The NA48 Collaboration, V. Fanti. 1999-09-13. A new measurement of direct CP violation in two pion decays of the neutral kaon. https://doi.org/10.1016/s0370-2693(99)01030-8

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