B and D meson decay constants from 2+1 flavor improved staggered simulations

Authors :: Neil, E. T.
Bailey, Jon A.
Bazavov, A.
Bernard, C.
Bouchard, C. M.
DeTar, C.
Di Pierro, M.
El-Khadra, A. X.
Evans, R. T.
Freeland, E.
Gamiz, E.
Gottlieb, Steven
Heller, U. M.
Hetrick, J. E.
Jain, R.
Kronfeld, A. S.
Laiho, J.
Levkova, L.
Mackenzie, P. B.
Oktay, M. B.
Simone, J. N.
Sugar, R.
Toussaint, D.
Van de Water, R. S.
Publication Year :: 2011
Publisher :: arXiv, 2011.
Abstract: We give an update on simulation results for the decay constants f_B, f_{B_s}, f_D and f_{D_s}. These decay constants are important for precision tests of the standard model, in particular entering as inputs to the global CKM unitarity triangle fit. The results presented here make use of the MILC (2+1)-flavor asqtad ensembles, with heavy quarks incorporated using the clover action with the Fermilab method. Partially quenched, staggered chiral perturbation theory is used to extract the decay constants at the physical point. In addition, we give error projections for a new analysis in progress, based on an extended data set.<br />Comment: 7 pages, 2 figures. Proceedings of the XXIX International Symposium on Lattice Field Theory - Lattice 2011, July 10-16, 2011, Squaw Valley, Lake Tahoe, California