An upper limit on the branching ratio for the decay K+ → π + νν¯ is set at 2.4 × 10−9 at the 90\% C.L. using pions in the kinematic region 214 MeV/c < Pπ < 231 MeV/c. An upper limit of 5.2 × 10−10 is found on the branching ratio for decays K+ → π+X0, where X0 is any massless, weakly interacting neutral particle. Limits are also set for cases where MX0 > 0.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy(all)