Measurement of Direct Cp Violation by Na48
نویسنده
چکیده
The NA48 experiment at the CERN SPS aims to search for direct CP /violation in the K system through the measurement of Re(ε/ε) with high accuracy. In 1999 the NA48 collaboration has published its first measurement based on 1997 data. The final result based on 1998 and 1999 data is presented in this article. The result, combined with 1997 data, Re(ε/ε) = (15.3 ± 2.6) × 10, definitely established direct CP violation.
منابع مشابه
Review of the NA48 CP violation measurements with neutral and charged kaons
The main results on the CP violation measurements with neutral and charged kaons from the NA48 experiment at the CERN SPS are reviewed in this paper. The direct CP violating parameter Re(ε′/ε) has been measured by NA48 from the decay rates of neutral kaons into pion pairs. The final result, based on the data collected in 1997, 1998, 1999 and 2001, clearly established the existence of direct CP ...
متن کاملMeasurement of the direct CP violation by NA48 experiment at CERN
The NA48 experiment at the CERN SPS accelerator aims to measure Re(ε′/ε), the direct CP violation parameter in K → 2π decays, to the precision of 2 × 10−4. In the year 1999, the NA48 collaboration has published its first measurement based on the 1997 data. The presented result is a preliminary measurement from data collected in the 1998 run which contain 2.5 times more KL → 2π decays than the 1...
متن کاملSEARCH FOR DIRECT CP VIOLATION IN K ± → π ± π + π − DECAYS BY NA48/2 a
First preliminary measurement of the direct CP-violating parameter Ag by the NA48/2 experiment at CERN SPS is presented. Using more than 1.6 billions of charged kaon decays into three charged pions, the charge asymmetry in the K
متن کاملMeasurement 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....
متن کاملMeasurement of Direct Cp Violation by the Na48 Experiment at Cern
CP violation occurs in the Standard Model through the imaginary phase in the CKM mixing matrix. An alternative mechanism, proposed shortly after the discovery of the effect, is a superweak interaction. The latter can be ruled out by experimental observation of direct CP violation, parametrized by ε. Theoretical calculations of ε within the Standard Model are hard, but most predictions give ε/ε ...
متن کامل