Effective Hamiltonian forΔS=1weak nonleptonic decays in the six-quark model

Frederick J. Gilman, Mark B. Wise
1979 Physical Review D, Particles and fields  
Strong-interaction corrections to the nonleptonic weak-interaction Hamiltonian are calculated in the leading-logarithmic approximation using quantum chromodynamics. Starting with a six-quark theory, the W boson, t quark, b quark, and c quark are successively considered as "heavy" and the effective Hamiltonian calculated. The resulting effective Hamiltonian for strangeness-changing nonleptonic decays involves u, d, and s quarks and has possible CP-violating pieces both in the usual (V -A) )& (V
more » ... usual (V -A) )& (V -A) terms and in induced, "penguin"-type terms. Numerically, the CP-violating compared to CP-conserving parts of the latter terms are close to results calculate/ on the basis of the lowest-order "penguin" diagram. from the mass matrix. It followed that the sixquark model yields predictions for the CPviolation parameters of the kaon system (in particular e'/e ) which are distinguishable from those of the superweak model. Two questions could be asked about the validity of using Fig. 1 to estimate the ratio of CP-violating to CP-conserving amplitudes. First. is the effect of multiple soft-gluon exchanges. This has been answered in Ref. 7 where it is shown how the local four-fermion structure of the effective Hami. ltonian is preserved despite the presence of 20 2392
doi:10.1103/physrevd.20.2392 fatcat:wu22lste7vho7a3j62wrxtd2vm