S. Chiba

K-π resonance and the strangeness violating weak interactions

Abstract It is pointed out that for the p-wave K-π resonance M, comparison of the rates of K + →e+ ν + π 0 and M + →K + + π 0 decays could provide us with useful information with respect to the value of the coupling constant of strangeness violating weak interactions and also to that of strong interaction of M. The results are consistent with the experimentally found low rate of Λ →p+e − + ν decay and also with the sharp backward peaking of the Λ° in the reaction π − + p→ Λ °+K 0 with high incident pion energy. The effects of the K-π resonances on the K → e+ ν + π decay are discussed and it is inferred that these effects are not important. The status of the strangeness violating weak interaction is discussed.

Σ−ΛRelative Parity and theΣ0→Λ0+γ+γDecay

It is shown that the π0-pole term predicts a large difference by nearly two to three orders of magnitude for the branching ratio of the Σ0→Λ0+2γ decay mode, depending upon the value of the Σ-Λ relative parity. It is further argued that this difference is not masked, even if we include other diagrams. It is thus suggested that a study of the branching ratio of the Σ0→Λ0+2γ decay may serve to determine the Σ-Λ relative parity.