Evidence for the decay K+ ---> pi+ neutrino anti-neutrino
Evidence for the decay K+ ---> pi+ neutrino anti-neutrino
An event consistent with the signature expected for the rare kaon decay K{sup +}{r_arrow}{pi}{sup +}{nu}{bar {nu}} has been observed. In the pion momentum region examined, 211{lt}P{lt}230 MeV/c , the backgrounds are estimated to contribute 0.08{plus_minus}0.03 events. If the event is due to K{sup +}{r_arrow}{pi}{sup +}{nu}{bar {nu}} , the branching ratio …