title: Precise determination of |V(us)| from lattice calculations of pseudoscalar decay constants.
abstract: Combining the ratio of experimental kaon and pion decay widths, Gamma(K-->munu (mu)(gamma))/Gamma(pi-->munu (mu)(gamma)), with a recent lattice gauge theory calculation of f(K)/f(pi) provides a precise value for the Cabibbo-Kobayashi-Maskawa quark mixing matrix element |V(us)|=0.2219(25) or if three generation unitarity is assumed |V(us)|=0.222 1(24). Comparison with other determinations of that fundamental parameter, implications, and an outlook for future improvements are given.
authors.affiliation: Brookhaven National Laboratory, Upton, NY 11973, USA.
authors.forename: William J
authors.initials: WJ
authors.lastname: Marciano