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Related papers: Three Topics in Renormalization and Improvement

200 papers

We report on non-perturbative computations of the improvement coefficient c_V and the renormalization factor Z_V of the vector current in three-flavour O(a) improved lattice QCD with Wilson quarks and tree-level Symanzik improved gauge…

High Energy Physics - Lattice · Physics 2018-04-18 Jochen Heitger , Fabian Joswig , Anastassios Vladikas , Christian Wittemeier

The topics covered by the lectures include Symanzik's effective continuum theory, O(a) improvement, chiral symmetry on the lattice and non-perturbative renormalization.

High Energy Physics - Lattice · Physics 2007-05-23 Martin Lüscher

We present results for the non-perturbative determination of the improvement and renormalization factors of the isovector axial current for lattice QCD with two flavors of dynamical Wilson quarks. The improvement and normalization…

High Energy Physics - Lattice · Physics 2007-05-23 Roland Hoffmann , Michele Della Morte , Francesco Knechtli , Rainer Sommer , Ulli Wolff

The reweighting method is applied to improve the chiral property of domain-wall fermions. One way to achieve this is to enlarge $L_s$, the size of fifth dimension, which controls the size of the induced chiral symmetry breaking. While this…

High Energy Physics - Lattice · Physics 2010-03-11 Tomomi Ishikawa , Yasumichi Aoki , Taku Izubuchi

We report on an ongoing non-perturbative computation of RI-MOM scheme renormalization constants for the lattice action with four dynamical flavours currently in use by ETMC. For this goal dedicated simulations with four degenerate sea quark…

High Energy Physics - Lattice · Physics 2015-03-17 P. Dimopoulos , R. Frezzotti , G. Herdoiza , K. Jansen , V. Lubicz , D. Palao , G. C. Rossi

The problem of unphysical zero modes in lattice QCD with Wilson fermions can be solved in a clean way by including a mass term proportional to $i \psibar \gamma_5 \tau^3 \psi$ in the standard lattice theory with Nf=2 mass degenerate Wilson…

High Energy Physics - Lattice · Physics 2015-06-25 Roberto Frezzotti , Pietro Antonio Grassi , Stefan Sint , Peter Weisz

We present the current status of our computation of quark bilinear renormalization constants for Wilson fermions and Symanzik improved gauge action. Computations are performed in Numerical Stochastic Perturbation Theory. Volumes range from…

High Energy Physics - Lattice · Physics 2010-02-03 M. Brambilla , F. Di Renzo , L. Scorzato

We compute non-perturbative renormalization constants of fermionic bilinears for the chirally improved lattice fermions in the quenched approximation of QCD. We address finite size effects and the influence of Gribov copies. Our results are…

High Energy Physics - Lattice · Physics 2014-11-17 Christof Gattringer , M. Göckeler , Philipp Huber , C. B. Lang

The non-normality of Wilson-type lattice Dirac operators has important consequences - the application of the usual concepts from the textbook (hermitian) quantum mechanics should be reconsidered. This includes an appropriate definition of…

High Energy Physics - Lattice · Physics 2015-06-25 I. Hip , Th. Lippert , H. Neff , K. Schilling , W. Schroers

Quantum Chromodynamics on a lattice with Wilson fermions and a chirally twisted mass term is considered in the framework of chiral perturbation theory. For two and three numbers of quark flavours, respectively, with non-degenerate quark…

High Energy Physics - Lattice · Physics 2010-12-23 Gernot Münster , Tobias Sudmann

We review a number of topics related to block variable renormalisation group transformations of quantum fields on the lattice, and to the emerging perfect lattice actions. We first illustrate this procedure by considering scalar fields.…

High Energy Physics - Lattice · Physics 2008-11-26 W. Bietenholz

In calculating hadronic contributions to precision observables for tests of the Standard Model in lattice QCD, the electromagnetic current plays a central role. Using a Wilson action with O($a$) improvement in QCD with $N_{\mathrm{f}}$…

High Energy Physics - Lattice · Physics 2019-02-20 Antoine Gerardin , Tim Harris , Harvey B. Meyer

I review some of the difficulties associated with chiral symmetry in the context of a lattice regulator. I discuss the structure of Wilson Fermions when the hopping parameter is in the vicinity of its critical value. Here one flavor…

High Energy Physics - Lattice · Physics 2009-10-22 Michael Creutz

We study the chiral properties of quenched domain wall fermions with several gauge actions. We demonstrate that the residual chiral symmetry breaking, which is present for a finite number of lattice sites in the fifth dimension ($L_s$), can…

High Energy Physics - Lattice · Physics 2009-11-07 Y. Aoki , T. Blum , N. Christ , C. Cristian , C. Dawson , T. Izubuchi , G. Liu , R. Mawhinney , S. Ohta , K. Orginos , A. Soni , L. Wu

We study the change of the QCD spectrum of low-lying mesons in the presence of an external magnetic field using Wilson fermions in the quenched approximation. Motivated by qualitative differences observed in the spectra of overlap and…

High Energy Physics - Lattice · Physics 2015-10-15 Gunnar Bali , Bastian B. Brandt , Gergely Endrodi , Benjamin Glaessle

We address the perturbative renormalization of massive lattice fermions. We derive expressions-valid to all orders in perturbation theory and for all values of the bare fermion mass-for the rest mass, the kinetic mass, and the wave-function…

High Energy Physics - Lattice · Physics 2010-11-19 Bartholomeus P. G. Mertens , Andreas S. Kronfeld , Aida X. El-Khadra

We study a systematic improvement of perturbation theory for gauge fields on the lattice; the improvement entails resumming, to all orders in the coupling constant, a dominant subclass of tadpole diagrams. This method, originally proposed…

High Energy Physics - Lattice · Physics 2009-11-11 M. Constantinou , H. Panagopoulos , A. Skouroupathis

We simulate two dimensional QED with two degenerate Wilson fermions and plaquette gauge action. As a consequence of the Mermin-Wagner theorem, in the continuum limit chiral symmetry is realized a la Wigner. This property affects also the…

High Energy Physics - Lattice · Physics 2009-11-11 Michele Della Morte , Magdalena Luz

In this work we calculate the renormalization of counterterms which arise in the lattice action of $N = 1$ Supersymmetric QCD (SQCD). In particular, the fine-tunings for quartic couplings are studied in detail through both continuum and…

High Energy Physics - Lattice · Physics 2024-09-17 Marios Costa , Herodotos Herodotou , Haralambos Panagopoulos

Lattice computations in the Hamiltonian formulation have so far mainly focused on staggered fermions. In these proceedings, we study Wilson fermions in the Hamiltonian formulation and propose a new method to determine the resulting mass…

High Energy Physics - Lattice · Physics 2023-10-19 Takis Angelides , Lena Funcke , Karl Jansen , Stefan Kühn