Abstract
We calculate the leptonic decay constants of and mesons in lattice QCD using staggered light quarks and Fermilab bottom and charm quarks. We compute the heavy-light-meson correlation functions on the MILC Asqtad-improved staggered gauge configurations, which include the effects of three light dynamical sea quarks. We simulate with several values of the light valence- and sea-quark masses (down to ) and at three lattice spacings (, 0.12, and 0.09 fm) and extrapolate to the physical up and down quark masses and the continuum using expressions derived in heavy-light-meson staggered chiral perturbation theory. We renormalize the heavy-light axial current using a mostly nonperturbative method such that only a small correction to unity must be computed in lattice perturbation theory, and higher-order terms are expected to be small. We use the two finer lattice spacings for our central analysis, and we use the third to help estimate discretization errors. We obtain , , , , and the flavor-breaking ratios and , where the numbers in parentheses are the total statistical and systematic uncertainties added in quadrature.
6 More- Received 18 January 2012
DOI:https://doi.org/10.1103/PhysRevD.85.114506
© 2012 American Physical Society