Charge Properties of theKMeson and Hyperon Decay Interaction

The question of the DELTA T involved in strange-particle decays is discussed in terms of universal Fermi interactions. The fundamental interactions considered contain DELTA T> 1/2 as suggested by both experimental and purely theoretical considerations. It is found that by assuming global symmetry in both the pion coupling and the weak coupling one may restrict the DELTA T to 1/2 in a class of processes involved in hyperon decay. These are the processes in which the real pion is given off externally. A symmetry may also be incorporated which forbids the decay XI /sup -/ ratory. N + pi . A breakdown of this symmetry is necessary to allow SIGMA /sup -/ decay. Reasons are developed for this breakdown to be manifested primarily in the P-wave part of SIGMA and LAMBDA decay. A consequence is that SIGMA /sup -/ decay should allow no parity nonconservation. The assumption of global symmetry enables one to connect SIGMA decay to LAMBDA decay. Fitting the decay rates in the suggested model yields a prediction of the A decay rate and asymmetry in agreement with experiment. Various ways of obtaining a more » selection rule prohibiting the theta /sup +/mode of K decay are discussed. These depend on symmetries which may be incorporated into an interaction containing DELTA T = 1/2, 3/2, and 5/2. (auth) « less