A precise measurement of the direct CP violation parameter Re ( ε ′ / ε )
نویسندگان
چکیده
The direct CP violation parameter Re(ε′/ε) 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 → ππ events collected during the 1998 and 1999 running periods, a result of Re(ε′/ε) = (15.0 ± 2.7)×10−4 has been obtained. The result combined with the published 1997 sample is Re(ε′/ε) = (15.3± 2.6)×10−4.
منابع مشابه
Measurement of ε′/ε from the NA48 experiment
Using data collected in 1998 by the NA48 experiment, a preliminary measurement of the direct CP violation parameter Re (ε/ε) is here presented, together with a discussion of the experimental method, data analysis and systematic studies. The result is Re (ε/ε) = (12.2± 4.9) × 10, and combined with the previously published NA48 result (based from data collected in 1997) gives Re (ε/ε) = (14.0± 4....
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تاریخ انتشار 2001