C.M. Maynard

Effects of nonperturbatively improved dynamical fermions in QCD at fixed lattice spacing

We present results for the static inter-quark potential, lightest glueballs, light hadron spectrum and topological susceptibility using a non-perturbatively improved action on a

Decay constants of B and D mesons from non-perturbatively improved lattice QCD

16^3\times 32

Improved B→πlνl form factors from the lattice

lattice at a set of values of the bare gauge coupling and bare dynamical quark mass chosen to keep the lattice size fixed in physical units (

The spectrum of Ds mesons from lattice QCD

\sim 1.7

Excited nucleon spectrum using a non-perturbatively improved clover fermion action

fm). By comparing these measurements with a matched quenched ensemble, we study the effects due to two degenerate flavours of dynamical quarks. With the greater control over residual lattice spacing effects which these methods afford, we find some evidence of charge screening and some minor effects on the light hadron spectrum over the range of quark masses studied (

Building the International Lattice Data Grid

M_{PS}/M_{V}\ge0.58

B to rho ell nu form factors in lattice QCD

). More substantial differences between quenched and unquenched simulations are observed in measurements of topological quantities.

Performance Evaluation of Mixed-Mode OpenMP/MPI Implementations

The decay constants of B and D mesons are computed in quenched lattice QCD at two dierent values of the coupling. The action and operators areO(a )i mproved with non-perturbative coecients where available. The results are fB = 218 +5 5 +5 41 MeV, fD = 220 +3 3 +2 24 MeV, fBs = 242 +4 4 +13 48 MeV, fDs = 241 +2 2 +7 30 MeV. Systematic errors are discussed in detail. Results for vector decay constants, avour symmetry breaking ratios of decay constants, the pseudoscalar-vector mass splitting and D meson masses are also presented.

Lattice QCD with mixed actions

Abstract We present the results of a lattice computation of the form factors for B 0 → π − l + ν l decays near zero-recoil. These results will allow a determination of the CKM matrix element | V ub | when measurements of the differential decay rate become available. We also provide models for extrapolation of the form factors and rate to the full recoil range. Our computation is performed in the quenched approximation to QCD on a 24 3 ×48 lattice at β =6.2, using a non-perturbatively O (a) -improved action. The masses of all light valence quarks involved are extrapolated to their physical values.

QCDml: First milestones for building an International Lattice Data Grid

The spectrum of orbitally excited