English
Related papers

Related papers: Overlap hypercube fermions in QCD with light quark…

200 papers

We present results from simulations of two flavors of dynamical overlap fermions on 8^4 lattices at three values of the sea quark mass and a lattice spacing of about 0.16 fm. We measure the topological susceptibility and the chiral…

High Energy Physics - Lattice · Physics 2009-11-11 Thomas DeGrand , Stefan Schaefer

Overlap fermions are particularly well suited to study the finite temperature dynamics of the chiral symmetry restoration transition of QCD, which might be just an analytic crossover. Using gauge field configurations on a 24^3x10 lattice…

High Energy Physics - Lattice · Physics 2008-11-26 V. Weinberg , E. -M. Ilgenfritz , K. Koller , Y. Koma , Y. Nakamura , G. Schierholz , T. Streuer

We present simulation results for the 2-flavour Schwinger model with dynamical Ginsparg-Wilson fermions. Our Dirac operator is constructed by inserting an approximately chiral hypercube operator into the overlap formula, which yields the…

High Energy Physics - Lattice · Physics 2008-11-26 Jan Volkholz , Wolfgang Bietenholz , Stanislav Shcheredin

In order to enhance our understanding of spectral functions in lattice QCD obtained with the help of the Maximum Entropy Method, we study meson spectral functions for lattice fermions with chiral symmetry. In particular we analyse lattice…

High Energy Physics - Lattice · Physics 2010-10-27 Gert Aarts , Justin Foley

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 present results of a hybrid Monte-Carlo algorithm for dynamical, $n_f=2$, four-dimensional QCD with overlap fermions. The fermionic force requires careful treatment, when changing topological sectors. The pion mass dependence of the…

High Energy Physics - Lattice · Physics 2009-11-10 Z. Fodor , S. D. Katz , K. K. Szabo

We present results on hadron masses and quark condensate from Neuberger's overlap fermion. The scaling and chiral properties and finite volume effects from this new Dirac operator are studied. We find that the generalized…

High Energy Physics - Lattice · Physics 2015-06-25 K. F. Liu , S. J. Dong , F. X. Lee , J. B. Zhang

We formulate Hamiltonian vector-like lattice gauge theory using the overlap formula for the spatial fermionic part, $H_f$. We define a chiral charge, $Q_5$ which commutes with $H_f$, but not with the electric field term. There is an…

High Energy Physics - Lattice · Physics 2007-05-23 Michael Creutz , Ivan Horváth , Herbert Neuberger

We study the quenched chiral behavior of the pion with mass as low as $\approx 180$ MeV. The calculation is done on a quenched lattice of size $16^3\times 28$ and $a = 0.2$ fm with 80 configurations using overlap fermions and an improved…

High Energy Physics - Lattice · Physics 2008-11-26 Terrence Draper , Shao-Jing Dong , Ivan Horvath , Frank Lee , Keh-Fei Liu , Nilmani Mathur , Jianbo Zhang

We perform dynamical QCD simulations with $n_f=2$ overlap fermions by hybrid Monte-Carlo method on $6^4$ to $8^3\times 16$ lattices. We study the problem of topological sector changing. A new method is proposed which works without…

High Energy Physics - Lattice · Physics 2009-11-11 G. I. Egri , Z. Fodor , S. D. Katz , K. K. Szabo

We compare the behavior of overlap fermions, which are chirally invariant, and of Wilson twisted mass fermions at full twist in the approach to the chiral limit. Our quenched simulations reveal that with both formulations of lattice…

We present a comparison of a number of iterative solvers of linear systems of equations for obtaining the fermion propagator in lattice QCD. In particular, we consider chirally invariant overlap and chirally improved Wilson (maximally)…

High Energy Physics - Lattice · Physics 2015-10-27 T. Chiarappa , K. Jansen , K. -I. Nagai , M. Papinutto , L. Scorzato , A. Shindler , C. Urbach , U. Wenger , I. Wetzorke

The overlap fermion offers the tremendous advantage of exact chiral symmetry on the lattice, but is numerically intensive. This can be made affordable while still providing large lattice volumes, by using coarse lattice spacing, given that…

High Energy Physics - Lattice · Physics 2014-11-17 Terrence Draper , Nilmani Mathur , Jianbo Zhang , Andrei Alexandru , Ying Chen , Shao-Jing Dong , Ivan Horvath , Frank Lee , Sonali Tamhankar

We test exact and approximate Ginsparg-Wilson fermions with respect to their chiral and scaling behavior in the 2-flavor Schwinger model. We first consider explicit approximate GW fermions in a short range, then we proceed to their chiral…

High Energy Physics - Lattice · Physics 2015-06-25 W. Bietenholz , I. Hip

We study the quenched chiral behavior of hadrons with the pseudoscalar mass as low as $\approx 280$ MeV. We look for quenched chiral logs in the pion mass, determine the renormalized quark mass, and observe quenched artifacts in the $a_0$…

High Energy Physics - Lattice · Physics 2008-11-26 Shao-Jing Dong , Terrence Draper , Ivan Horvath , Frank Lee , Jianbo Zhang

Overlap fermions preserve a remnant of chiral symmetry on the lattice. They are a powerful tool to investigate the topological structure of the vacuum of Yang-Mills theory and full QCD. Recent results concerning the localization of…

High Energy Physics - Lattice · Physics 2011-04-01 E. -M. Ilgenfritz , K. Koller , Y. Koma , G. Schierholz , V. Weinberg

The phase diagram for the compact lattice QED with Wilson fermions is shown. We discuss different methods for the calculation of the 'pion' mass $m_{\pi}$ near the chiral transition point $\kappa_c(\beta )$.

High Energy Physics - Lattice · Physics 2009-10-28 A. Hoferichter , V. K. Mitrjushkin , M. Müller-Preussker

Adopting a mixed action approach, we report here results on hadron spectra containing one or more charm quarks. We use overlap valence quarks on a background of 2+1+1 flavor HISQ gauge configurations generated by the MILC collaboration. We…

High Energy Physics - Lattice · Physics 2013-12-12 S. Basak , S. Datta , A. T. Lytle , M. Padmanath , P. Majumdar , N. Mathur

Using the non-perturbative renormalization technique, we calculate the renormalization factors for quark bilinear operators made of overlap fermions on the lattice. The background gauge field is generated by the JLQCD and TWQCD…

High Energy Physics - Lattice · Physics 2010-04-06 J. Noaki , T. W. Chiu , H. Fukaya , S. Hashimoto , H. Matsufuru , T. Onogi , E. Shintani , N. Yamada

Overlap fermions are a powerful tool for investigating the chiral and topological structure of the vacuum and the thermal states of QCD. We study various chiral and topological aspects of the finite temperature phase transition of N_f=2…

High Energy Physics - Lattice · Physics 2007-05-23 V. Weinberg , E. -M. Ilgenfritz , K. Koller , Y. Koma , G. Schierholz , T. Streuer