进一步寻找衰变K⁺→π⁺νν；

Further search for the decay K+-->pi(+)nunu;

作者信息

Adler S, Atiya MS, Chiang IH, Diwan MV, Frank JS, Haggerty JS, Jain V, Kettell SH, Kycia TF, Li KK, Littenberg LS, Ng C, Strand RC, Witzig C, Kazumori M, Komatsubara TK, Kuriki M, Muramatsu N, Otomo A, Sugimoto S, Inagaki T, Kabe S, Kobayashi M, Kuno Y, Sato T, Shinkawa T

机构信息

Brookhaven National Laboratory, Upton, New York 11973, USA.

出版信息

Phys Rev Lett. 2000 Apr 24;84(17):3768-70. doi: 10.1103/PhysRevLett.84.3768.

DOI:10.1103/PhysRevLett.84.3768

PMID:11019201

Abstract

A search for additional evidence for the rare kaon decay K+-->pi(+)nunu; has been made with a new data set comparable in sensitivity to the previous exposure that produced a single event. No new events were found in the pion momentum region examined, 211<P<229 MeV/c. Including a reanalysis of the original data set, the backgrounds were estimated to contribute 0.08+/-0.02 events. Based on one observed event, the new branching ratio is B(K+-->pi(+)nunu;) = 1.5(+3.4)(-1.2)x10(-10).

摘要

对罕见的K介子衰变K⁺→π⁺νν进行了额外证据的搜索；使用了一个新的数据集，其灵敏度与产生单个事件的先前曝光相当。在所研究的π介子动量区域211<P<229 MeV/c中未发现新事件。包括对原始数据集的重新分析，背景估计贡献0.08±0.02个事件。基于一个观测到的事件，新的分支比为B(K⁺→π⁺νν)=1.5(+3.4)(-1.2)×10⁻¹⁰ 。