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Search for the K(L) --> PI0 PI0 E+ E- Decay in the KTeV Experiment

KTeV Collaboration·A. Alavi-Harati
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Abstract

The recent discovery of a large CP violating asymmetry in K(L) --> PI+ PI- E+ E- mode has prompted us to seach for the associated K(L) --> PI0 PI0 E+ E- decay mode in the KTeV-E799 experiment at Fermilab. In 2.7E+11 K(L) decays, one candidate event has been observed with an expected background of 0.3 event, resulting in an upper limit for the K(L) --> PI0 PI0 E+ E- branching ratio of 6.6E-09 at the 90% confidence level.

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KTeV Collaboration, A. Alavi-Harati. 2002-10-24. Search for the K(L) --> PI0 PI0 E+ E- Decay in the KTeV Experiment. https://doi.org/10.1103/physrevlett.89.211801

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