LATTICE QCD WITH DOMAIN-WALL QUARKS AND APPLICATIONS TO WEAK MATRIX-ELEMENTS

Using domain wall fermions, we estimate B-K(mu approximate to 2 GeV) = 0.628(47) in quenched QCD which is consistent with previous calculati ons. At 6/g(2) = 6.0 and 5.85 we find the ratio f(K)/m(rho) in agreeme nt with the experimental value, within errors. These results support e xpectations that O(a) errors are exponentially suppressed in low energ y (E much less than a(-1)) observables, and indicate that domain wall fermions have good scaling behavior at relatively strong couplings. We also demonstrate that the axial current numerically satisfies the lat tice analog of the usual continuum axial Ward identity.