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Related papers: Aspects of QCD Vacuum Structure

200 papers

We study the two-point Topological Charge Density Correlator (TCDC) in lattice QCD with two degenerate flavours of naive Wilson fermions and unimproved Wilson gauge action at two values of lattice spacings and different volumes, for a range…

High Energy Physics - Lattice · Physics 2012-12-03 Abhishek Chowdhury , Asit K. De , A. Harindranath , Jyotirmoy Maiti , Santanu Mondal

We investigate the interplay between topological charge and the spectrum of the fermion matrix in lattice-QED_2 using analytic methods and Monte Carlo simulations with dynamical fermions. A new theorem on the spectral decomposition of the…

High Energy Physics - Lattice · Physics 2009-10-30 C. R. Gattringer , I. Hip , C. B. Lang

Chiral perturbation theory predicts that in quantum chromodynamics (QCD), light dynamical quarks suppress the gauge-field topological susceptibility of the vacuum. The degree of suppression depends on quark multiplicity and masses. It…

Overlap fermions have an exact chiral symmetry on the lattice and are thus an appropriate tool for investigating the chiral and topological structure of the QCD vacuum. We study various chiral and topological aspects of quenched gauge field…

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

We discuss properties of thermal Quantum Chromodynamics obtained by means of lattice simulations with overlap fermions. This fermion discretisation preserves chiral symmetry at finite lattice spacing. We present details of the formulation…

High Energy Physics - Lattice · Physics 2025-10-30 Z. Fodor , A. Yu. Kotov , T. G. Kovacs , K. K. Szabo

We study the vacuum topology of 2+1 flavor QCD above the chiral crossover transition, at $T \lesssim 1.2~T_c$, on lattices of size $32^3\times 8$. Since overlap fermions have exact chiral symmetry and an index theorem even on a finite…

High Energy Physics - Lattice · Physics 2020-08-12 Rasmus N. Larsen , Sayantan Sharma , Edward Shuryak

The topological susceptibility is one of the few physical quantities that directly measure the properties of the QCD vacuum. Chiral perturbation theory predicts that in the small quark mass limit the topological susceptibility depends…

High Energy Physics - Lattice · Physics 2009-11-07 Anna Hasenfratz

Global topological charge decorrelates very slowly or even freezes in fine lattice simulations. On the other hand, its local fluctuations are expected to survive and lead to the correct physical results as long as the volume is large…

High Energy Physics - Lattice · Physics 2014-11-17 JLQCD collaboration , H. Fukaya , S. Aoki , G. Cossu , S. Hashimoto , T. Kaneko , J. Noaki

We study some of the local CP-odd and magnetic properties of the non-Abelian vacuum with use of overlap fermions within the quenched lattice gauge theory. Among these properties are the following: inhomogeneous spatial distribution of the…

High Energy Physics - Lattice · Physics 2013-03-01 V. V. Braguta , P. V. Buividovich , T. Kalaydzhyan , M. I. Polikarpov

APE smearing and overlap-Dirac operator are combined to filter QCD vacuum configurations. The results obtained from overlap fermions and improved 5Li cooling are compared, both of them exhibit structures of dilute liquid of instanton.…

High Energy Physics - Lattice · Physics 2009-11-11 Z. Q. Wang , X. F. Lu , Fan Wang

We systematically compare filtering methods used to extract topological structures on SU(3) lattice configurations. We show that there is a strong correlation of the topological charge densities obtained by APE and Stout smearing. To get…

High Energy Physics - Lattice · Physics 2015-03-13 Falk Bruckmann , Florian Gruber , Andreas Schäfer

We perform an analysis of the topological and chiral vacuum structure of four-dimensional QCD on the lattice at finite temperature. From correlation functions we show the existence of local correlations between the topological charge…

High Energy Physics - Lattice · Physics 2009-10-30 Markus Feurstein , Harald Markum , Stefan Thurner

Recently, we have pointed out that sign-coherent 4-dimensional structures can not dominate topological charge fluctuations in QCD vacuum at all scales. Here we show that an enhanced lower-dimensional coherence is possible. In pure SU(3)…

High Energy Physics - Lattice · Physics 2017-08-23 I. Horvath , S. J. Dong , T. Draper , K. F. Liu , N. Mathur , F. X. Lee , H. B. Thacker , J. B. Zhang

We present results on QCD with four dynamical flavors in the temperature range $0.9 \lesssim T/T_c \lesssim 2$. We have performed lattice simulations with Wilson fermions at maximal twist and measured the topological charge with gluonic and…

High Energy Physics - Lattice · Physics 2018-03-14 Florian Burger , Ernst-Michael Ilgenfritz , Maria Paola Lombardo , Michael Müller-Preussker , Anton Trunin

Three complementary views on the QCD vacuum structure, all based on eigenmodes of the overlap operator, are reported in their interrelation: (i) spectral density, localization and chiral properties of the modes, (ii) the possibility of…

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

The non-trivial ground-state vacuum fields of QCD form the foundation of matter. Here we examine the centre vortices identified within the ground-state fields of lattice QCD. We aim to understand the manner in which dynamical fermions in…

High Energy Physics - Lattice · Physics 2023-01-11 Derek Leinweber , James Biddle , Waseem Kamleh , Adam Virgili

We discuss the utility of low-lying Dirac eigenmodes for studying the nature of topological charge fluctuations in QCD. The implications of previous results using the local chirality histogram method are discussed, and the new results using…

High Energy Physics - Lattice · Physics 2008-11-26 S. J. Dong , T. Draper , I. Horvath , N. Isgur , F. X. Lee , J. McCune , J. B. Zhang , H. B. Thacker

Screening of the topological charge due to he fermion-induced interactions is an important phenomenon, closely related with the resolution of the strong CP and U(1) problems. We study the mechanism of such screening in a 'correlated…

High Energy Physics - Lattice · Physics 2014-11-17 E. V. Shuryak , J. J. M. Verbaarschot

Overlap fermions implement exact chiral symmetry on the lattice and are thus an appropriate tool for investigating the chiral and topological structure of the QCD vacuum. We study various chiral and topological aspects on…

High Energy Physics - Lattice · Physics 2009-11-11 E. -M. Ilgenfritz , K. Koller , Y. Koma , G. Schierholz , T. Streuer , V. Weinberg

We study the $\theta$-vacuum of QCD using two-flavor chiral perturbation theory ($\chi$PT) in the presence of a uniform, background magnetic field calculating the magnetic field-dependent free energy density, the topological density, the…

High Energy Physics - Phenomenology · Physics 2022-01-26 Prabal Adhikari