R. S. Van De Water

B- and D-meson decay constants from three-flavor lattice QCD

We calculate the leptonic decay constants ofB (s) andD (s) 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 congurations which include the eects of three light dynamical sea quarks. We simulate with several values of the light valence- and sea-quark masses (down to ms=10) and at three lattice spacings (a 0.15, 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 obtain f B+ = 196:9(8:9) MeV, fBs = 242:0(9:5) MeV, f D+ = 218:9(11:3) MeV, fDs = 260:1(10:8) MeV, and the SU(3) avor-breaking ratios fBs =fB = 1:229(26) and fDs =fD = 1:188(25), where the numbers in parentheses are the total statistical and systematic uncertainties added in quadrature.

B →d ν form factors at nonzero recoil and |Vcb | from 2+1 -flavor lattice QCD

We present the first unquenched lattice-QCD calculation of the hadronic form factors for the exclusive decay

B→πlν semileptonic form factor from three-flavor lattice QCD: A model-independent determination of |Vub|

\overline{B}\ensuremath{\rightarrow}D\ensuremath{\ell}\overline{\ensuremath{\nu}}

B(s)0-mixing matrix elements from lattice QCD for the Standard Model and beyond

at nonzero recoil. We carry out numerical simulations on 14 ensembles of gauge-field configurations generated with

Lattice QCD ensembles with four flavors of highly improved staggered quarks

2+1

Refining new-physics searches in B→Dτν with lattice QCD.

flavors of asqtad-improved staggered sea quarks. The ensembles encompass a wide range of lattice spacings (approximately 0.045 to 0.12 fm) and ratios of light (up and down) to strange sea-quark masses ranging from 0.05 to 0.4. For the

Scaling studies of QCD with the dynamical highly improved staggered quark action

b

B̄→D*ℓν̄ form factor at zero recoil from three-flavor lattice QCD: A model independent determination of |Vcb|

and

B→Kl+l−decay form factors from three-flavor lattice QCD

c

Refining New-Physics Searches inB→Dτνwith Lattice QCD

valence quarks we use improved Wilson fermions with the Fermilab interpretation, while for the light valence quarks we use asqtad-improved staggered fermions. We extrapolate our results to the physical point using rooted staggered heavy-light meson chiral perturbation theory. We then parametrize the form factors and extend them to the full kinematic range using model-independent functions based on analyticity and unitarity. We present our final results for