We have collected a 43 event sample of the decay KL → e+e-μ+μ- with negligible backgrounds and measured its branching ratio to be (2.62 ± 0.40 ± 0.17) × 10-9. 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±e± μ∓μ∓ at B(KL → e±e±μ∓ μ∓) ≤ 1.23 × 10-10, assuming a uniform phase space distribution.
ASJC Scopus subject areas
- Physics and Astronomy(all)