English
Related papers

Related papers: Chirally improving Wilson fermions

200 papers

The pion masses and the pion decay constant are calculated to 1-loop order in twisted mass Wilson chiral perturbation theory, assuming a large pion mass splitting and tuning to maximal twist. Taking the large mass splitting at leading order…

High Energy Physics - Lattice · Physics 2010-12-13 Oliver Bar

We present an adaptive multigrid solver for application to the non-Hermitian Wilson-Dirac system of QCD. The key components leading to the success of our proposed algorithm are the use of an adaptive projection onto coarse grids that…

High Energy Physics - Lattice · Physics 2010-12-02 R. Babich , J. Brannick , R. C. Brower , M. A. Clark , T. A. Manteuffel , S. F. McCormick , J. C. Osborn , C. Rebbi

QCD thermodynamics is considered using Wilson fermions in the fixed scale approach. The temperature dependence of the renormalized chiral condensate, quark number susceptibility and Polyakov loop is measured at four lattice spacings…

High Energy Physics - Lattice · Physics 2015-06-05 S. Borsanyi , S. Durr , Z. Fodor , C. Hoelbling , S. D. Katz , S. Krieg , D. Nogradi , B. C. Toth , N. Trombitas , K. K. Szabo

The flavour singlet axial Ward identity with Osterwalder-Seiler twisted mass Wilson fermion action is studied on a finite lattice, with finite fermion mass and the Wilson parameter r up to 1. Approach to the infinite volume chiral limit and…

High Energy Physics - Lattice · Physics 2010-02-26 Asit K. De , A. Harindranath , Santanu Mondal

Iterating renormalization group transformations for lattice fermions the Wilson action is driven to fixed points of the renormalization group. A line of fixed points is found and the fixed point actions are computed analytically. They are…

High Energy Physics - Lattice · Physics 2009-10-22 U. -J. Wiese , HLRZ Juelich

We propose improved estimators to compute the reweighting factors which are needed for lattice QCD calculations that rely on twisted-mass reweighting for the light quark contribution and the Rational Hybrid Monte Carlo (RHMC) algorithm for…

High Energy Physics - Lattice · Physics 2024-03-19 Simon Kuberski

The chiral properties of lattice fermions can be improved by altering either their fermion-gauge coupling or the pure gauge part of the action (or both). Using both perturbation theory and nonperturbative simulation, we compare a simple…

High Energy Physics - Lattice · Physics 2016-09-01 Thomas DeGrand , Anna Hasenfratz , Tamas G. Kovacs

A serious difficulty in conventional lattice field theory calculations is the coupling between the chiral and continuum limits. With both staggered and Wilson fermions, the chiral limit cannot be realized without first taking the limit of…

In QCD chiral symmetry is explicitly broken by quark masses, the effect of which can be described reliably by chiral perturbation theory. Effects of explicit chiral symmetry breaking by the lattice regularisation of the Dirac operator,…

High Energy Physics - Lattice · Physics 2011-01-27 Nigel Cundy , Tony Kennedy , Andreas Schäfer

Recently various new concepts for the construction of Dirac operators in lattice Quantum Chromodynamics (QCD) have been introduced. These operators satisfy the so-called Ginsparg-Wilson condition (GWC), thus obeying the Atiyah-Singer index…

High Energy Physics - Lattice · Physics 2011-07-19 Christof Gattringer , C. B. Lang

We present the results of an extended scaling test of quenched Wilson twisted mass QCD. We fix the twist angle by using two definitions of the critical mass, the first obtained by requiring the vanishing of the pseudoscalar meson mass m_PS…

High Energy Physics - Lattice · Physics 2007-05-23 K. Jansen , M. Papinutto , A. Shindler , C. Urbach , I. Wetzorke

Quenched lattice QCD calculations with Wilson-type fermions at small quark masses are impeded by exceptional configurations. We show how this problem can be resolved in a practicable way without changing the physics in the chiral limit.

High Energy Physics - Lattice · Physics 2008-11-26 M. Göckeler , A. Hoferichter , R. Horsley , D. Pleiter , P. Rakow , G. Schierholz , P. Stephenson

We present the comparison of the analytical microscopic spectral density for lattice QCD with $N_{\rm f}=2$ twisted mass fermions with the one obtained on the lattice utilizing configurations produced by the ETM collaboration. We extract…

High Energy Physics - Lattice · Physics 2015-11-02 Krzysztof Cichy , Elena Garcia-Ramos , K. Splittorff , Savvas Zafeiropoulos

The Symanzik analysis of correlators in lattice QCD with maximally twisted Wilson fermions reveals that there exist cutoff artifacts which tend to become large as the quark mass gets small. We show that these effects can be reduced to a…

High Energy Physics - Lattice · Physics 2007-05-23 Giancarlo Rossi , Roberto Frezzotti , Guido Martinelli , Mauro Papinutto

The overlap Dirac operator, which satisfies the Ginsparg-Wilson relation, realizes exact chiral symmetry on the lattice without any unphysical doubler modes. To perform the path integrals, one should, however, note that the overlap fermion…

High Energy Physics - Lattice · Physics 2007-05-23 Hidenori Fukaya

We make several observations concerning the low quark mass region with Wilson fermions and how this is connected with the epsilon regime in the continuum. A transition from tiny cutoff effects to rather large discretization errors would…

High Energy Physics - Lattice · Physics 2009-02-27 Andrea Shindler

We present a first scaling test of twisted mass QCD with pure Wilson quarks for a twisting angle of pi/2. We have computed the vector meson mass and the pseudoscalar decay constant for different values of beta at fixed value of r_0 m_PS.…

High Energy Physics - Lattice · Physics 2009-11-10 Karl Jansen , Andrea Shindler , Carsten Urbach , Ines Wetzorke

We study the phase structure and the chiral limit of $4d$ compact lattice QED with Wilson fermions (both dynamical and quenched). We use the standard Wilson gauge action and also a modified one suppressing lattice artifacts. Different…

High Energy Physics - Lattice · Physics 2009-10-22 A. Hoferichter , V. K. Mitrjushkin , M. Müller-Preussker , T. Neuhaus , H. Stüben

A few years ago some attention has been given to a fermionic action on the lattice, with a Wilson-like term which is chirally invariant but breaks the hypercubic space-time lattice symmetry. This action describes two Dirac fields in the…

High Energy Physics - Lattice · Physics 2009-10-22 Mario Pernici

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…