Observation of CP Violation in K(L)->pi+pi-e+e- Decays

Abstract

We report the first observation of a manifestly CP violating effect in the K(L)->pi+pi-e+e- decay mode. A large asymmetry was observed in the distribution of these decays in the CP-odd and T-odd angle phi between the decay planes of the e+e- and pi+pi- pairs in the K(L) center of mass system. After acceptance corrections, the overall asymmetry is found to be 13.6+-2.5 (stat) +-1.2 (syst)%. This is the largest CP-violating effect yet observed integrating over the entire phase space of a mode and the first such effect observed in an angular variable.

4 pages 4 figures submitted to prl

References in corpus (2)

• K_L to π^+ π^- e^+ e^-
• Final State Interactions and CP Violation in $K_L\to {\pi }^{+}{\pi }^{-}{e}^{+}{e}^{-}$

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