相关论文: Highly Improved Staggered Quarks on the Lattice, w…
We report on recent progress in employing the Highly Improved Staggered Quark (HISQ) action introduced by the HPQCD/UKQCD collaboration in simulations with dynamical fermions. The HISQ action is an order $a^2$ Symanzik-improved action with…
We present results from our simulations of quantum chromodynamics (QCD) with four flavors of quarks: u, d, s, and c. These simulations are performed with a one-loop Symanzik improved gauge action, and the highly improved staggered quark…
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…
We describe recent progress on generation of gauge configurations using the Highly Improved Staggered Quark (HISQ) action that was designed by the HPQCD/UKQCD collaboration. The HISQ action requires two levels of smearing with a…
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…
We present an update of our study of high temperature QCD with three flavors of quarks, using a Symanzik improved gauge action and the Asqtad staggered quark action. Simulations are being carried out on lattices with Nt=4, 6 and 8 for the…
The improved staggered quark action has enabled breakthrough calculations of QCD with three light dynamical quarks. The largest remaining $a^2$ scaling violations come from "taste-changing" interactions, which are significantly reduced over…
We report on a study of QCD thermodynamics with three flavors of quarks, using a Symanzik improved gauge action and the Asqtad O(a^2) improved staggered quark action. Simulations were carried out with lattice spacings 1/4T, 1/6T and 1/8T…
We report on investigations of the chiral and deconfinement aspects of the finite temperature transition in 2+1 flavor QCD using the Highly Improved Staggered Quark (HISQ) action on lattices with temporal extent $N_\tau=6$ and $N_\tau=8$.…
We use a relativistic highly improved staggered quark action to discretize charm quarks on the lattice. We calculate the masses and the dispersion relation for heavy-heavy and heavy-light meson states, and show that for lattice spacings…
We study the lattice spacing dependence, or scaling, of physical quantities using the highly improved staggered quark (HISQ) action introduced by the HPQCD/UKQCD collaboration, comparing our results to similar simulations with the asqtad…
We present preliminary results from exploring the phase diagram of finite temperature QCD with three degenerate flavors and with two light flavors and the mass of the third held approximately at the strange quark mass. We use an order…
We present preliminary results from exploring the phase diagram of finite temperature QCD with three degenerate flavors and with two light flavors and the mass of the third held approximately at the strange quark mass. We use an order…
In highly improved staggered quark (HISQ) simulations by the HPQCD, MILC, and Fermilab Lattice collaborations, both the light quarks and the charm quark are staggered. We extend chiral perturbation theory for staggered quarks to include…
We explore the first stage of the Symanzik improvement program for lattice Dirac fermions, namely the construction of doubler-free, highly improved classical actions on isotropic as well as anisotropic lattices (where the temporal lattice…
We present results from a systematic perturbative investigation of taste-changing in improved staggered quarks. We show one-loop taste-changing interactions can be removed perturbatively by an effective four-quark term and calculate the…
We investigate a class of actions for lattice QCD with staggered quarks aimed at reducing the flavour symmetry violations associated with using staggered fermions. These actions replace the gauge field link fields in the quark action with…
We present an update of results from the HPQCD collaboration on charm physics using the Highly Improved Staggered Quark action. This includes a precise determination of m_c using moments of current-current correlators combined with…
We report on investigations of the chiral and deconfinement aspects of the finite temperature transition in 2+1 flavor QCD using the Highly Improved Staggered Quark (HISQ) action on lattices with temporal extent $N_\tau=6$ and $N_\tau=8$.…
We introduce a new class of actions for staggered quarks in lattice QCD which significantly reduce flavour symmetry violations in the pion mass spectrum. An action introduced by the MILC collaboration for the same purpose is seen to be a…