Improved measurement of the K+-->pi+nunu; branching ratio

V V Anisimovsky; A V Artamonov; B Bassalleck; B Bhuyan; E W Blackmore; D A Bryman; S Chen; I-H Chiang; I-A Christidi; P S Cooper; M V Diwan; J S Frank; T Fujiwara; J Hu; A P Ivashkin; D E Jaffe; S Kabe; S H Kettell; M M Khabibullin; A N Khotjantsev; P Kitching; M Kobayashi; T K Komatsubara; A Konaka; A P Kozhevnikov; Yu G Kudenko; A Kushnirenko; L G Landsberg; B Lewis; K K Li; L S Littenberg; J A Macdonald; J Mildenberger; O V Mineev; M Miyajima; K Mizouchi; V A Mukhin; N Muramatsu; T Nakano; M Nomachi; T Nomura; T Numao; V F Obraztsov; K Omata; D I Patalakha; S V Petrenko; R Poutissou; E J Ramberg; G Redlinger; T Sato; T Sekiguchi; T Shinkawa; R C Strand; S Sugimoto; Y Tamagawa; R Tschirhart; T Tsunemi; D V Vavilov; B Viren; N V Yershov; Y Yoshimura; T Yoshioka; E949 Collaboration

doi:10.1103/PhysRevLett.93.031801

Improved measurement of the K+-->pi+nunu; branching ratio

Phys Rev Lett. 2004 Jul 16;93(3):031801. doi: 10.1103/PhysRevLett.93.031801. Epub 2004 Jul 12.

Authors

V V Anisimovsky¹, A V Artamonov, B Bassalleck, B Bhuyan, E W Blackmore, D A Bryman, S Chen, I-H Chiang, I-A Christidi, P S Cooper, M V Diwan, J S Frank, T Fujiwara, J Hu, A P Ivashkin, D E Jaffe, S Kabe, S H Kettell, M M Khabibullin, A N Khotjantsev, P Kitching, M Kobayashi, T K Komatsubara, A Konaka, A P Kozhevnikov, Yu G Kudenko, A Kushnirenko, L G Landsberg, B Lewis, K K Li, L S Littenberg, J A Macdonald, J Mildenberger, O V Mineev, M Miyajima, K Mizouchi, V A Mukhin, N Muramatsu, T Nakano, M Nomachi, T Nomura, T Numao, V F Obraztsov, K Omata, D I Patalakha, S V Petrenko, R Poutissou, E J Ramberg, G Redlinger, T Sato, T Sekiguchi, T Shinkawa, R C Strand, S Sugimoto, Y Tamagawa, R Tschirhart, T Tsunemi, D V Vavilov, B Viren, N V Yershov, Y Yoshimura, T Yoshioka; E949 Collaboration

Affiliation

¹ Institute for Nuclear Research RAS, 60 October Revolution Prospect 7a, 117312 Moscow, Russia.

PMID: 15323812
DOI: 10.1103/PhysRevLett.93.031801

Abstract

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.