Related papers: Non-perturbative improvement of stout-smeared thre…
We present an exploratory study for the nonperturbative determination of the coefficient of the ${\cal O}(a)$ improvement term to the Wilson action, $c_{SW}$. Following the work by L\"{u}scher et al., we impose the PCAC relation as a…
We have determined the non-perturbative O(a)-improvement coefficient c_sw for four flavors of Wilson quarks with the plaquette gauge action in a range of beta >= 5. The data are fitted with several Pade approximation formulae to get an…
We calculate the perturbative value of the free energy in QCD on the lattice. This quantity is directly related to the average plaquette. Our calculation is done to 3 loops using the clover action for fermions; the results are presented for…
The eigenvalue spectra of staggered fermions with an Adams and/or Hoelbling mass term are studied. The chiralities of the eigenmodes reflect whether the chirality linked to the unflavored approximate (\gamma_5 \times 1) or the flavored…
We generate $2+1$ flavor QCD configurations near the physical point on a $96^4$ lattice employing the 6-APE stout smeared Wilson clover action with a nonperturbative $c_{\rm SW}$ and the Iwasaki gauge action at $\beta=1.82$. The physical…
We perform the non-perturbative renormalization of matrix elements of the static-light axial current by a computation of its scale dependence in lattice QCD with two flavours of massless O(a) improved Wilson quarks. The regularization…
I have performed scaling tests using quenched spectroscopy of a family of fermion actions which have a hypercubic kinetic term, gauge connections built of smeared links, and an anomalous magnetic moment term. These actions show improved…
We non-perturbatively determine the renormalization constant and the improvement coefficients relating the renormalized current and subtracted quark mass in O(a) improved two-flavour lattice QCD. We employ the Schr\"odinger functional…
Clover improvement is the standard choice for lattice simulations of QCD, when the lattice artefacts coming from Wilson fermions have to be reduced. However, the clover improvement is not limited to QCD, but can be applied to a wider range…
The ALPHA collaboration has determined the O(a) improved Wilson quark action for lattice spacings $a\leq 0.1$ fm, in the quenched approximation. We extend this result to coarser lattices, $a\leq 0.17$ fm, and calculate the hadron spectrum…
We resolve contradictions in the literature concerning the origins and size of unphysical flavor-changing strong interactions generated by the staggered-quark discretization of QCD. We show that the leading contributions are tree-level in…
A Lie-algebra based recipe for smoothing gauge links in lattice field theory is presented, building on the matrix logarithm. With or without hypercubic nesting, this LOG/HYL smearing yields fat links which are differentiable w.r.t. the…
We report on our studies of the renormalization of flavor singlet quark bilinear operators in lattice QCD. The renormalization constants are determined non-perturbatively using gauge field ensembles with Nf=2 dynamical clover improved…
We report results of simulations of the $2+1d$ Thirring model with $N$ fermion flavors, defined on a lattice using domain wall fermions. This approach is devised to respect as far as possible the underlying U($2N$) symmetry of the continuum…
We report the results of our quenched lattice simulations of the Wilson action with a nonperturbatively determined clover term at beta=6.2 and compare them with those of the standard Wilson action at the same beta value.
APE smearing the links in the irrelevant operators of clover fermions (Fat-Link Irrelevant Clover (FLIC) fermions) provides significant improvement in the condition number of the Hermitian-Dirac operator and gives rise to a factor of two…
The Brillouin action is a Wilson-like lattice fermion action with a 81-point stencil, which was found to ameliorate the Wilson action in many respects. The Sheikholeslami-Wohlert coefficient $c_\mathrm{SW}$ of the clover improvement term…
First results from simulations of improved actions for both gauge fields and staggered fermion fields in three dimensional QCD are presented. This work provides insight into some issues of relevance to lattice theories in four dimensions.…
In this talk we give an overview of the 3D phase diagram of two-flavour non-zero temperature lattice QCD with twisted-mass Wilson fermions and a tree-level Symanzik-improved gauge action. We present a first feasibility study at maximal…
Taste symmetry violations in staggered fermion formulations correlate strongly with the cut-off (lattice spacing) dependence in thermodynamic quantities. Better taste symmetry on the lattice can be achieved either by decreasing the lattice…