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A precise measurement of the direct CP violation parameter Re(epsilon'/epsilon)

NA48 Collaboration
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Abstract

The direct CP violation parameter Re(epsilon'/epsilon) has been measured from the decay rates of neutral kaons into two pions using the NA48 detector at the CERN SPS. With 3.3 million KL->pi0pi0 events collected during the 1998 and 1999 running periods, a result of Re(epsilon'/epsilon) = (15.0 +- 2.7)x10-4 has been obtained. The result combined with the published 1997 sample is Re(epsilon'/epsilon) = (15.3 +- 2.6)x10-4.

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NA48 Collaboration. 2001-10-11. A precise measurement of the direct CP violation parameter Re(epsilon'/epsilon). https://doi.org/10.1007/s100520100822

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