Related papers: Cutoff effects in meson spectral functions
We study cutoff effects at tree-level of perturbation theory for maximally twisted mass Wilson, overlap and the recently proposed Creutz fermions. We demonstrate that all three kind of lattice fermions exhibit the expected O(a^2) scaling…
I review recent Lattice results. In particular, the confinement mechanism and string breaking, glueballs and hybrid mesons as well as light hadron spectroscopy are discussed.
Using domain wall fermions, we estimate $B_K(\mu\approx 2 GeV)=0.628(47)$ in quenched QCD which is consistent with previous calculations. At $\gbeta=6.0$ and 5.85 we find the ratio $f_K/m_\rho$ in agreement with the experimental value,…
I present a survey of calculations of the excited $N^*$ spectrum in lattice QCD. I then describe recent advances aimed at extracting the momentum-dependent phase shifts from lattice calculations, notably in the meson sector, and the…
Lattice QCD calculations of baryon forces are performed for the first time with (almost) physical quark masses. $N_f = 2+1$ dynamical clover fermion gauge configurations are generated at the lattice spacing of $a \simeq 0.085$ fm on a $(96…
We study the spectra of charmonia, charmed mesons, singly and doubly charmed baryons using Lattice QCD, with 2+1 flavours of fermions. In the case of mesons, we include higher spin states, while for baryons, both positive and negative…
We use lattice methods to evaluate from first principles the spectrum of hybrid mesons produced by gluonic excitations in quenched QCD with quark masses near the strange quark mass. For the spin-exotic mesons with $J^{PC}=1^{-+},\ 0^{+-}$,…
In this talk we present the results obtained from a study of ${\cal O}(2000)$ (quenched) lattice configurations from the APE collaboration, at $6.0\le\beta\le 6.4$, using both the Wilson and the SW-Clover fermion action. We determine the…
A study of the chiral behavior of pseudoscalar masses and decay constants is carried out in quenched lattice QCD with Wilson fermions. Using the modified quenched approximation (MQA) to cure the exceptional configuration problem, accurate…
We simulate two dimensional QED with two degenerate Wilson fermions and plaquette gauge action. As a consequence of the Mermin-Wagner theorem, in the continuum limit chiral symmetry is realized a la Wigner. This property affects also the…
The QCD-coupling is a necessary input in the computation of many observables, and the parametric error on input parameters can be a dominant source of uncertainty. The coupling can be extracted by comparing high order perturbative…
Progress in calculating the spectrum of excited baryons and mesons in lattice QCD is described. Correlation matrices of sets of spatially-extended hadron operators have been studied and their effectiveness in facilitating the extraction of…
We present the first study of the light hadron spectrum and decay constants for quenched QCD using an O(a)-improved nearest-neighbour Wilson fermion action at \beta=6.2. We compare the results with those obtained using the standard Wilson…
We report on simulations of quenched QCD using domain wall fermions, where we focus on basic questions about the formalism and its ability to produce expected low energy hadronic physics for light quarks. The work reported here is on…
We derive the asymptotic lattice spacing dependence $a^n[2b_0\bar{g}^2(1/a)]^{\hat{\Gamma}_i}$ relevant for spectral quantities of lattice QCD, when using Wilson, O$(a)$ improved Wilson or Ginsparg-Wilson quarks. We give some examples for…
We study the expectation value of the phase of the fermion determinant for Wilson lattice fermions with chemical potential. We use quenched SU(3) ensembles and implement a recently proposed exact dimensional reduction of the fermion…
We compute the light hadron mass spectrum at beta=5.7 using the O(a) improved Sheikholeslami-Wohlert (SW) fermion action with two choices of the clover coefficient: the classical value, c=1, and a mean-field or tadpole-improved estimate…
The domain wall fermion formulation exhibits full chiral symmetry for finite lattice spacing except for the effects of mixing between the domain walls. Close to the continuum limit these symmetry breaking effects should be described by a…
It has been shown that in the twisted mass formulation of Lattice QCD at maximal twist large cutoff effects are generated when the quark mass becomes of O(a Lambda_QCD^2). In general, these effects can be suppressed in two ways: either by…
A brief overview of the lattice technique of studying QCD is presented. Recent results from the UKQCD Collaboration's simulations with dynamical quarks are then presented. In this work, the calculations are all at a fixed lattice spacing…