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Related papers: Numerical Tests of the Improved Fermilab Action

200 papers

We report on our study of light hadron spectrum and quark masses in QCD with two flavors of dynamical quarks. Simulations are made with the plaquette gauge action and the non-perturbatively $O(a)$ improved Wilson quark action. We simulate 5…

Masses of positive and negative parity excited nucleons and hyperons are calculated in quenched lattice QCD using an O(a^2) improved gluon action and a fat-link clover fermion action in which only the irrelevant operators are constructed…

High Energy Physics - Lattice · Physics 2010-03-04 W. Melnitchouk , J. N. Hedditch , D. B. Leinweber , A. G. Williams , J. M. Zanotti , J. B. Zhang

We present the light-flavor quark masses and low energy constants using the 2+1 flavor full-QCD ensembles with stout smeared clover fermion action and Symanzik gauge actions. Both the fermion and gauge actions are tadpole improved…

High Energy Physics - Lattice · Physics 2024-01-09 Zhi-Cheng Hu , Bo-Lun Hu , Ji-Hao Wang , Ming Gong , Liuming Liu , Peng Sun , Wei Sun , Wei Wang , Yi-Bo Yang , Dian-Jun Zhao

Tempering is used to change the quark mass while remaining in equilibrium between the trajectories of a standard hybrid Monte Carlo simulation of four flavours of staggered fermions. The algorithm is faster for small enough quark masses,…

High Energy Physics - Lattice · Physics 2007-05-23 G. Boyd

We develop an improved lattice action for heavy quarks based on Brillouin-type fermions, that have excellent energy-momentum dispersion relation. The leading discretization errors of $O(a)$ and $O(a^2)$ are eliminated at tree-level. We…

High Energy Physics - Lattice · Physics 2015-06-11 Yong-Gwi Cho , Shoji Hashimoto , Andreas Jüttner , Takashi Kaneko , Marina Marinkovic , Jun-Ichi Noaki , Justus Tobias Tsang

We apply a recent proposal to speed up the Hybrid-Monte-Carlo simulation of systems with dynamical fermions to two flavor QCD with clover-improvement. For our smallest quark masses we see a speed-up of more than a factor of two compared…

High Energy Physics - Lattice · Physics 2009-11-07 M. Hasenbusch , K. Jansen

We simulate Quantum Chromodynamics in four Euclidean dimensions with two (degenerate mass) flavors of dynamical quarks. The Dirac operator is the so-called chirally improved operator that has been studied so far in quenched calculations. We…

High Energy Physics - Lattice · Physics 2007-05-23 C. B. Lang , Pushan Majumdar , Wolfgang Ortner

We propose to determine the coefficients in the Fermilab heavy quark action by matching the finite-volume, off-shell, gauge-fixed propagator and vertex functions with those determined in the exact, relativistic theory. The matching…

High Energy Physics - Lattice · Physics 2009-11-10 Huey-Wen Lin

We test the scaling behaviour of Wilson, hypercube, maximally twisted mass and overlap fermion actions in dynamical simulations of the 2-dimensional massive Schwinger model. We also present possibilities to simulate overlap fermions…

High Energy Physics - Lattice · Physics 2007-05-23 Nils Christian , Karl Jansen , Kei-ichi Nagai , Beatrix Pollakowski

We present recent results for meson screening masses with quenched Wilson fermions above and below the confinement- deconfinement phase transition. The action used in the simulation is the Sheikholeslami Wohlert action. The quark masses are…

High Energy Physics - Lattice · Physics 2007-05-23 P. Schmidt with E. Laermann

We explore sea quark effects in the light hadron mass spectrum in a simulation of two-flavor QCD using the nonperturbatively O(a)-improved Wilson fermion action. In order to identify finite-size effects, light meson masses are measured on…

We investigate the impact of including a dynamical charm quark on the properties of light hadrons. Our study uses gauge ensembles generated with the tadpole-improved Symanzik gauge action, comparing 2+1+1 flavor (HISQ fermion) ensembles at…

High Energy Physics - Lattice · Physics 2026-03-05 Tong-Wei Lin , Zun-Xian Zhang , Mengchu Cai , Hai-Yang Du , Bolun Hu , Xiangyu Jiang , Xiao-Lan Meng , Ji-Hao Wang , Peng Sun , Yi-Bo Yang , Dian-Jun Zhao

The Fat-Link Irrelevant Clover (FLIC) fermion action provides a new form of nonperturbative O(a) improvement and allows efficient access to the light quark-mass regime. FLIC fermions enable the construction of the nonperturbatively…

High Energy Physics - Lattice · Physics 2010-03-04 J. M. Zanotti , D. B. Leinweber , A. G. Williams , J. B. Zhang

Improved Kogut-Susskind quark actions containing repeatedly smeared links are studied to address the issue of flavor symmetry restoration. As a measure of the flavor symmetry restoration the mass spectrum of all the pions is computed. We…

High Energy Physics - Lattice · Physics 2009-10-31 Kostas Orginos , Doug Toussaint

Perturbative estimates of operator coefficients for improved lattice actions are becoming increasingly important for precision simulations of many hadronic observables. Following previous work by Dimm, Lepage, and Mackenzie, we consider the…

High Energy Physics - Lattice · Physics 2009-10-30 Howard D. Trottier , G. Peter Lepage

The Fat-Link Irrelevant Clover (FLIC) fermion action provides a new form of nonperturbative O(a) improvement and allows efficient access to the light quark-mass regime. FLIC fermions enable the construction of the nonperturbatively…

High Energy Physics - Lattice · Physics 2010-03-04 J. M. Zanotti , S. Boinepalli , D. B. Leinweber , A. G. Williams , J. B. Zhang

We simulate two dynamical, mass degenerate light quarks on 16^3x32 lattices with a spatial extent of 2.4 fm using the Chirally Improved Dirac operator. The simulation method, the implementation of the action and signals of equilibration are…

High Energy Physics - Lattice · Physics 2009-11-06 Christof Gattringer , Christian Hagen , C. B. Lang , Markus Limmer , Daniel Mohler , Andreas Schäfer

We discuss a mixed-action approach in which sea quarks are regularised using non-perturbatively ${\rm O}(a)$ improved Wilson fermions, while a fully-twisted tmQCD action is used for valence quarks. In this setup, automatic ${\rm O}(a)$…

High Energy Physics - Lattice · Physics 2018-04-18 Gregorio Herdoíza , Carlos Pena , David Preti , José Ángel Romero , Javier Ugarrio

We report results for the interaction measure, pressure and energy density for nonzero temperature QCD with 2+1 flavors of improved staggered quarks. In our simulations we use a Symanzik improved gauge action and the Asqtad $O(a^2)$…

High Energy Physics - Lattice · Physics 2008-11-26 C. Bernard , T. Burch , C. DeTar , Steven Gottlieb , L. Levkova , U. M. Heller , J. E. Hetrick , R. Sugar , D. Toussaint

QCD is investigated at finite temperature using Wilson fermions in the fixed scale approach. A 2+1 flavor stout and clover improved action is used at four lattice spacings allowing for control over discretization errors. The light quark…