7 v 1 2 2 A ug 2 00 1 Branching Ratio Measurement of the decay K L → e + e − μ + μ −
نویسندگان
چکیده
We have collected a 43 event sample of the decay KL → e eμμ with negligible backgrounds and measured its branching ratio to be (2.62± 0.40± 0.17)×10. We see no evidence for CP violation in this decay. In addition, we set the 90% confidence upper limit on the combined branching ratios for the lepton flavor violating decays KL → e eμμ at B(KL → e eμμ) ≤ 1.23 × 10, assuming a uniform phase space distribution. PACS numbers: 13.85.Rm, 13.25.Es, 14.40.Aq, 14.80.Ly Typeset using REVTEX
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