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Related papers: Chirally improving Wilson fermions

200 papers

We show at the example of the matrix element between pion states of a twist-2, non-singlet operator that Wilson twisted mass fermions allow to compute this phenomenologically relevant quantitiy at small pseudo scalar masses of O(270 MeV).…

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

We compute fermionic observables relevant to the study of chiral symmetry in quenched QCD using the Overlap-Dirac operator for a wide range of the fermion mass. We use analytical results to disentangle the contribution from exact zero modes…

High Energy Physics - Lattice · Physics 2009-10-31 Robert G. Edwards , Urs M. Heller , Rajamani Narayanan

A transformation is devised to convert any lattice Dirac fermion operator into a Ginsparg-Wilson Dirac fermion operator. For the standard Wilson-Dirac lattice fermion operator, the transformed new operator is local, free of O(a) lattice…

High Energy Physics - Lattice · Physics 2011-02-16 Ting-Wai Chiu

We present evidence for improvement with tadpole improved clover fermions based on an analysis of the chiral behavior of $B_K$ and the quark condensate. Also presented are a comparison of the mass splittings in the baryon octet and…

High Energy Physics - Lattice · Physics 2010-05-27 Rajan Gupta

We introduce a lattice QCD mixed action approach that employs Wilson-type quarks in the sea and valence sectors. The sea sector is based on gauge ensembles with $N_{\rm f}=2+1$ flavours of non-perturbatively O($a$)-improved Wilson fermions…

Renormalizability of a lattice chiral fermion is studied at one loop level in the overlap formulation in four dimensions. The fermion chirality is examined including the self-energy corrections due to gauge interactions. Divergent terms…

High Energy Physics - Lattice · Physics 2009-10-30 Atsushi Yamada

It has been shown recently that Dirac operators satisfying the Ginsparg-Wilson relation provide a solution of the chirality problem in QCD at finite lattice spacing. We discuss different ways to construct these operators and their…

High Energy Physics - Lattice · Physics 2011-07-19 Ferenc Niedermayer

By employing a twisted mass term, we compare recent results from lattice calculations of Nf=2 dynamical Wilson fermions with Wilson Chiral Perturbation Theory (WChPT). The final goal is to determine some combinations of Gasser-Leutwyler Low…

High Energy Physics - Lattice · Physics 2010-12-23 L. Scorzato , F. Farchioni , P. Hofmann , K. Jansen , I. Montvay , G. Munster , M. Papinutto , E. E. Scholz , A. Shindler , N. Ukita , C. Urbach , U. Wenger , I. Wetzorke

Partially twisted boundary conditions are widely used for improving the momentum resolution in lattice computations of hadronic correlation functions. The method is however expensive since every additional twist requires computing…

High Energy Physics - Lattice · Physics 2021-12-17 Nils Asmussen , Alessandro Barone , Andreas Jüttner

The standard QCD action is improved by the addition of irrelevant operators built with chiral composites. An effective Lagrangian is derived in terms of auxiliary fields, which has the form of the phenomenological chiral Lagrangians. Our…

High Energy Physics - Lattice · Physics 2007-05-23 Sergio Caracciolo , Fabrizio Palumbo , Roberto Scimia

The graphene-inspired fermion actions recently proposed by Creutz and Borici have sparked interest in the use of non-orthogonal lattices in lattice QCD. These fermion actions have the desired chiral symmetry and have the minimal doubling…

High Energy Physics - Lattice · Physics 2009-08-20 Michael I. Buchoff

In the last century the non-perturbative regularization of chiral fermions was a long-standing problem. We review how this problem was finally overcome by the formulation of a modified but exact form of chiral symmetry on the lattice. This…

High Energy Physics - Lattice · Physics 2011-09-28 Wolfgang Bietenholz

We study the impact of explicit chiral symmetry breaking of Wilson fermions on mesonic correlators in the epsilon-regime using Wilson chiral perturbation theory (WChPT). We generalize the epsilon-expansion of continuum ChPT to nonzero…

High Energy Physics - Lattice · Physics 2009-03-27 Oliver Bar , Silvia Necco , Stefan Schaefer

Quantum Chromodynamics on a lattice with Wilson fermions and a chirally twisted mass term for two degenerate quark flavours is considered in the framework of chiral perturbation theory. The pion masses and decay constants are calculated in…

High Energy Physics - Lattice · Physics 2010-12-23 Gernot Münster , Christian Schmidt , Enno E. Scholz

We construct a family of Ginsparg-Wilson Hamiltonians with improved chiral properties, starting from a construction of Creutz-Horvath-Neuberger that provides a doubler-free Hamiltonian lattice regularization for Dirac fermions in even…

High Energy Physics - Lattice · Physics 2025-05-28 Hersh Singh

The fermion determinant and the chiral anomaly of lattice Dirac operator D on a finite lattice are investigated. The condition for D to reproduce correct chiral anomaly at each site of a finite lattice for smooth background gauge fields is…

High Energy Physics - Lattice · Physics 2007-05-23 Ting-Wai Chiu

We present our result for the $K\to\pi\pi$ decay amplitudes for both the $\Delta I=1/2$ and $3/2$ processes with the improved Wilson fermion action. Expanding on the earlier works by Bernard {\it et al.} and by Donini {\it et al.}, we show…

High Energy Physics - Lattice · Physics 2015-10-14 N. Ishizuka , K. -I. Ishikawa , A. Ukawa , T. Yoshié

We propose an extended Quantum Chromodynamics (XQCD) Lagrangian in which the fermions are coupled to elementary scalar %$\sigma$ and $\pi$ fields through a Yukawa coupling which preserves chiral invariance. Our principle motivation is to…

High Energy Physics - Lattice · Physics 2009-10-22 Richard C. Brower , Yue Shen , Chung-I Tan

I review the lattice formulations of vector-like gauge theories (e.g. QCD) with domain-wall/overlap fermions, and discuss how to optimize the chiral symmetry for any finite $ N_s $ (sites in the fifth dimension). In this formulation, quark…

High Energy Physics - Lattice · Physics 2011-02-16 Ting-Wai Chiu

We compute the lattice spacing corrections to the spectral density of the Hermitean Wilson Dirac operator using Wilson Chiral Perturbation Theory at NLO. We consider a regime where the quark mass $m$ and the lattice spacing $a$ obey the…

High Energy Physics - Lattice · Physics 2015-05-27 S. Necco , A. Shindler