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arXiv · hep-ex/9810018

Observation of the decay mode K_L -> pi^+ pi^- e^+ e^-

Y. Takeuchi·Y. Hemmi·H. Kurashige·Y. Matono·K. Murakami·T. Nomura·H. Sakamoto·N. Sasao·M. Suehiro·Y. Fukushima·Y. Ikegami·T. T. Nakamura·T. Taniguchi·M. Asai
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Abstract

We report on results of an experimental search for the K_L -> pi^+ pi^- e^+ e^- decay mode. We found 13.5 +- 4.0 events and determined its branching ratio to be (4.4 +- 1.3(stat) +- 0.5(syst))*10^{-7}. The result agrees well with the theoretical prediction.

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Y. Takeuchi, Y. Hemmi, H. Kurashige, Y. Matono, K. Murakami, T. Nomura, H. Sakamoto, N. Sasao, M. Suehiro, Y. Fukushima, Y. Ikegami, T. T. Nakamura, T. Taniguchi, M. Asai. 1998-10-08. Observation of the decay mode K_L -> pi^+ pi^- e^+ e^-. https://doi.org/10.1016/s0370-2693(98)01359-8

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