Note on the nonleptonic hyperon decays in SU(3)

Using a s-u-channel-symmetric weak Hamiltonian (8(X)27) and summing intermediate states to be nonexotic, the authors obtain most of the observed features, such as the Delta I=1/2 rule and the Lee-Sugawara sum rule, for parity-violating (pv) as well as parity-conserving (pc) decays of (1/2)/sup +/ hyperons. In addition two sum rules Sigma /sub +//sup +/=0 and square root 2 Sigma /sub +//sup +/- Sigma /sub 0//sup +/= square root 3 Lambda /sub -//sup 0/ in pv and pc modes, respectively, and also obtained, which are well satisfied experimentally. For Omega /sup -/ to Xi + pi decays, however, the Delta I=1/2 rule does not follow. Recent CERN data on this mode do indicate about 20% violation of the Delta I=1/2 rule. (11 refs).