Improved measurement of the K+-->pi+nunu; branching ratio.
An additional event near the upper kinematic limit for K+-->pi(+)nunu; has been observed by experiment E949 at Brookhaven National Laboratory. Combining previously reported and new data, the branching ratio is B(K+-->pi(+)nunu;)=(1.47(+1.30)(-0.89))x10(-10) based on three events observed in the pion momentum region 211<P<229 MeV/c. At the measured central value of the branching ratio, the additional event had a signal-to-background ratio of 0.9.
Institute for Nuclear Research RAS, 60 October Revolution Prospect 7a, 117312 Moscow, Russia.
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Anisimovsky
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Artamonov
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Bassalleck
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Bhuyan
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Blackmore
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Bryman
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Chen
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Chiang
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Cooper
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Diwan
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Frank
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Fujiwara
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Kabe
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Kitching
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Kobayashi
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Konaka
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Kozhevnikov
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Kudenko
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Kushnirenko
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Landsberg
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Lewis
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Littenberg
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Macdonald
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Mildenberger
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Miyajima
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Mizouchi
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Muramatsu
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Nomachi
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Numao
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Obraztsov
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Omata
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Petrenko
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Poutissou
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Ramberg
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Redlinger
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Sato
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Shinkawa
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Strand
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Sugimoto
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Tschirhart
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Tsunemi
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Viren
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