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Related papers: Proposal for Topologically Unquenched QCD

200 papers

We estimate the quark-mass dependence of the topological susceptibility with dynamical overlap and clover fermions. Unquenching effects on the susceptibility turn out to be well approximated by a reweighting of a quenched ensemble with a…

High Energy Physics - Lattice · Physics 2015-06-25 Tamas G. Kovacs

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 extend a technique for the chiral extrapolation of hadron masses calculated with dynamical fermions to those generated by quenched simulations. The method ensures the correct leading and next-to-leading non-analytic behaviour for either…

High Energy Physics - Lattice · Physics 2007-05-23 R. D. Young , D. B. Leinweber , A. W. Thomas , S. V. Wright

We simulate $N_f=2+1$ QCD at the physical point combining open and periodic boundary conditions in a parallel tempering framework, following the original proposal by M. Hasenbusch for $2d$ $\mathrm{CP}^{N-1}$ models, which has been recently…

High Energy Physics - Lattice · Physics 2024-09-04 Claudio Bonanno , Giuseppe Clemente , Massimo D'Elia , Lorenzo Maio , Luca Parente

The thesis will present results in Quantum Chromo Dynamics (QCD) with dynamical lattice fermions. The topological susceptibilty in QCD is determined, the calculations are carried out with dynamical overlap fermions. The most important…

High Energy Physics - Lattice · Physics 2008-01-03 K K Szabo

A chiral fermion action allows one to do very clean studies of chiral symmetry breaking in QCD. I will briefly describe how to compute with the overlap action (relatively) cheaply, and then turn to physics: Low modes of the Dirac operator…

High Energy Physics - Lattice · Physics 2007-05-23 Thomas DeGrand

We report first calculations of the topological susceptibility measured using the field theoretic method on SU(3) gauge configurations produced by the UKQCD collaboration with two flavours of dynamical, improved, Wilson fermions. Using…

High Energy Physics - Lattice · Physics 2015-06-25 A. Hart , M. Teper

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

A new multifermion formulation of lattice QCD is proposed. The model is free of spectrum doubling and preserves all nonanomalous chiral symmetries up to exponentially small corrections. It is argued that a small number of fermion fields may…

High Energy Physics - Lattice · Physics 2009-10-31 A. A. Slavnov

We investigate the topological susceptibility of the QCD vacuum with two flavours of dynamical staggered fermions on the lattice both at zero and finite temperature. At zero temperature we study the dependence of the signal on the fermion…

High Energy Physics - Lattice · Physics 2015-06-25 B. Alles , M. D'Elia , A. Di Giacomo

We study quenched QCD just above the phase transition temperature using overlap Fermions. Exact zero modes of the overlap operator are localized. Chiral symmetry is restored, as indicated by the behavior of the chiral condensate after…

High Energy Physics - Lattice · Physics 2015-06-25 R. V. Gavai , Sourendu Gupta , R. Lacaze

We explore the properties of low lying eigenmodes of fermions in the quenched approximation of lattice QCD. The fermion action is a recently proposed overlap action and has exact chiral symmetry. We find that chiral zero-eigenvalue modes…

High Energy Physics - Lattice · Physics 2009-10-31 Thomas DeGrand , Anna Hasenfratz

We calculate the chiral condensate of QCD at infinite coupling as a function of the number of fundamental fermion flavours using a lattice diagrammatic approach inspired by recent work of Tomboulis, and other work from the 80's. We outline…

High Energy Physics - Lattice · Physics 2015-02-18 Alexander S. Christensen , Joyce C. Myers , Peter D. Pedersen , Jan Rosseel

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 topological properties of full QCD with four flavours of dynamical staggered fermions. In particular the topological susceptibility is measured and the problem of the determination of its first derivative is discussed.

High Energy Physics - Lattice · Physics 2015-06-25 B. Alles , M. D'Elia , A. Di Giacomo

Chiral perturbation theory predicts that in quantum chromodymamics light dynamical quarks suppress the topological (instanton) susceptibility. We investigate this suppression through direct numerical simulation using the Asqtad improved…

High Energy Physics - Lattice · Physics 2008-11-26 C. Bernard , T. DeGrand , C. DeTar , Steven Gottlieb , E. Gregory , A. Hart , A. Hasenfratz , Urs Heller , J. Hetrick , J. Osborn , R. Sugar , D. Toussaint

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 study the improvement of simulations of QCD with dynamical Wilson fermions by combining the Hybrid Monte Carlo algorithm with parallel tempering. As an indicator for decorrelation we use the topological charge.

High Energy Physics - Lattice · Physics 2015-06-25 E. -M. Ilgenfritz , Werner Kerler , H. Stüben

We study thermalization, hydrodynamization, and chemical equilibration in out-of-equilibrium Quark-Gluon Plasma starting from various initial conditions using QCD effective kinetic theory, valid at weak coupling. In non-expanding systems…

High Energy Physics - Phenomenology · Physics 2019-04-30 Aleksi Kurkela , Aleksas Mazeliauskas

Non-compact QED3 is simulated both in the quenched and unquenched cases. In particular, we investigate the restoration of chiral symmetry at finite temperature. We also compute the zero temperature spectrum of the theory, including (in the…

High Energy Physics - Lattice · Physics 2009-10-22 J. B. Kogut , J. -F. Lagae