06 04 7 v 1 2 4 Ju n 20 03 LBL - 1034 , IIT - HEP - 03 / 1 Measurement of Decay Parameters for Ξ − → Λ π − Decay
نویسندگان
چکیده
Based on 1.35 million polarized Ξ − events, we measure the parameter φ Ξ to be −1.61 • ±2.66 • ±0.37 • for the Ξ − → Λπ − decay. New results for the parameters β Ξ and γ Ξ are also presented. Assuming that the CP-violating phase-shift difference is negligible, we deduce the strong phase-shift difference between the P-wave and S-wave amplitudes of the Λπ final state to be 3.17 • ± 5.28 • ± 0.73 •. This strong phase-shift difference reduces the theoretical uncertainty in estimating the level of CP violation in Ξ-hyperon decay.
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