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Search for the Decay K_L -> pi^0 nu nubar using pi^0 -> e^+ e^- gamma

A. Alavi-Harati
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Abstract

We report on a search for the decay K_L -> pi^0 nu nubar, carried out as a part of E799-II, a rare K_L decay experiment at Fermilab. Within the Standard Model, the K_L -> pi^0 nu nubar decay is dominated by direct CP violating processes, and thus an observation of the decay implies confirmation of direct CP violation. Due to theoretically clean calculations, a measurement of B(K_L -> pi^0 nu nubar) is one of the best ways to determine the CKM parameter eta. No events were observed, and we set an upper limit B(K_L -> pi^0 nu nubar) < 5.9 times 10^-7 at the 90% confidence level.

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A. Alavi-Harati. 1999-07-13. Search for the Decay K_L -> pi^0 nu nubar using pi^0 -> e^+ e^- gamma. https://doi.org/10.1103/physrevd.61.072006

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