FIRST AND SECOND CLASS WEAK HADRONIC CURRENTS AND THEIR IMPLICATIONS FOR KL3 DECAYS IN AN EXTENDED CABIBBO MODEL

Within the framework of a generalized Cabibbo model for the weak hadronic current in which the current is allowed to transform like an arbitrary mixture of SU(3) multiplets, thus accomodating possible ΔS = -ΔQ, ΔS = 2, and ΔI = 3 2 transitions, the concept of a first and second class strangeness non-changing, CP conserving current is extended to the strangeness changing, CP violating case. Using the experimental information on the branching ratio Γ (K- → π0e-ν)/Γ(KL → π+e-ν), predictions are made for the quantity (1-|x|2)/|1-x|2, where x ≡ A(K0 → π+e-ν/ A(K0 → π+e-ν) and the decay ratio Γ(η → π+e-ν)/ Γ(π- → π0e-ν) assuming that the current is either first or second class. It is found that a first class current leads to predictions which are in good agreement with experiment. © 1969.