A new measurement of direct CP violation in the neutral kaon system

• DOI: 10.1016/0370-2693(93)91599-i
• Publication Date: 2003-08-01T01:24:25Z
• Authors: G.D. Barr; P. Buchholz; R. Carosi; D. Coward; D. Cundy; N. Doble; L. Gatignon; V. Gibson; P. Grafström; R. Hagelberg; J. van der Lans; H.N. Nelson; H. Wahl; K.J. Peach; H. Blümer; R. Heinz; K. Kleinknecht; P. Mayer; B. Panzer; B. Renk; H. Rohrer; H.G. Sander; A. Wagner; E. Augé; D. Fournier; P. Heusse; L. Iconomidou-Fayard; I. Harrus; O. Perdereau; A.C. Schaffer; L. Serin; L. Bertanza; A. Bigi; P. Calafiura; M. Calvetti; M.C. Carrozza; R. Casali; C. Cerri; R. Fantechi; I.G. Mannelli; V.M. Marzulli; A. Nappi; G. Pierazzini; M. Holder; A. Kreutz; G. Quast; M. Rost; R. Werthenbach; G. Zech
• Keywords: Particle and Plasma Physics; Molecular; Nuclear; Atomic; Nuclear & Particles Physics; Mathematical Physics; Astronomical and Space Sciences

A new measurement of the ratio of the CP-violating amplitudes for KL → 2π0 and KL → π+π− is reported. The measured value for R = ∣η00/η+-∣2 is 0.9878±0.0026±0.0030, where the first error is the statistical uncertainty and the second is the estimate of the systematic uncertainty. This gives a value for the parameter describing direct CP violation: Re ϵ'/ϵ = (2.0 ± 0.7) × 10−3.