Feasibility of Lattice QCD Simulations for Weak Decay Processes

Abstract

The computation of a class of processes involving a weak decay vertex and one, two, or three external hadrons is discussed. The use of an extended source propagator for the quark allows calculation of matrix elements using only one to two orders of magnitude more computer time than mass calculations. Thus in the quenched approximation these calculations appear feasible within the current generation of lattice QCD simulations. In particular, semi-leptonic decay processes for heavy flavors offers lattice QCD an opportunity to contribute to the testing of the Cabbibo-Kobayashi-Maskawa six quark mixing hypothesis in the standard electroweak model of Glashow, Salam and Weinberg.