English
Related papers

Related papers: Topological susceptibility from the twisted mass D…

200 papers

We discuss the computation of the topological susceptibility using the method of spectral projectors and dynamical twisted mass fermions. We present our analysis concerning the O(a)-improvement of the topological susceptibility and we show…

High Energy Physics - Lattice · Physics 2013-12-13 Krzysztof Cichy , Elena Garcia-Ramos , Karl Jansen , Andrea Shindler

We study the 'spectral projector' method for the computation of the chiral condensate and the topological susceptibility, using $N_f=2+1+1$ dynamical flavors of maximally twisted mass Wilson fermions. In particular, we perform a study of…

High Energy Physics - Lattice · Physics 2012-03-29 K. Cichy , V. Drach , E. Garcia-Ramos , K. Jansen

We compare lattice QCD determinations of topological susceptibility using a gluonic definition from the gradient flow and a fermionic definition from the spectral projector method. We use ensembles with dynamical light, strange and charm…

We compute the topological susceptibility of $N_f=2+1$ QCD with physical quark masses in the high-temperature phase, using numerical simulations of the theory discretized on a space-time lattice. More precisely we estimate the topological…

We present the results of our computation of the chiral condensate with $N_f=2$ and $N_f=2+1+1$ flavours of maximally twisted mass fermions. The condensate is determined from the Dirac operator spectrum, applying the spectral projector…

High Energy Physics - Lattice · Physics 2013-12-20 Krzysztof Cichy , Elena Garcia-Ramos , Karl Jansen

We study the topological charge in $N_f=2$ QCD at finite temperature using M\"obius domain-wall fermions. The susceptibility $\chi_t$ of the topological charge defined either by the index of overlap Dirac operator or a gluonic operator is…

High Energy Physics - Lattice · Physics 2018-04-18 S. Aoki , Y. Aoki , G. Cossu , H. Fukaya , S. Hashimoto , K. Suzuki

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…

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 apply the spectral projector method, recently introduced by Giusti and L\"uscher, to compute the chiral condensate using $N_f=2$ and $N_f=2+1+1$ dynamical flavors of maximally twisted mass fermions. We present our results for several…

High Energy Physics - Lattice · Physics 2013-12-13 Krzysztof Cichy , Elena Garcia-Ramos , Karl Jansen , Andrea Shindler

As a test of the chiral properties of the improved Asqtad (staggered fermion) action, we have been measuring the topological susceptibility as a function of quark masses for 2 + 1 dynamical flavors. We report preliminary results, which show…

We investigate topology in lattice simulations of QCD with two flavours of dynamical Wilson fermions. At various sea quark masses we find reasonable agreement between results for the topological charge from fermionic and gluonic…

High Energy Physics - Lattice · Physics 2008-11-26 Gunnar S. Bali , Norbert Eicker , Thomas Lippert , Hartmut Neff , Boris Orth , Klaus Schilling , Thorsten Struckmann , Jochen Viehoff

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

Using a reweighting technique combined with a low-mode truncation of the fermionic determinant, we estimate the quark-mass dependence of the QCD topological susceptibility with overlap fermions. In contrast to previous lattice simulations…

High Energy Physics - Lattice · Physics 2009-09-25 Tamas G. Kovacs

The $\epsilon$-regime of dilaton chiral perturbation theory is introduced. We compute the dilaton mass, the chiral condensate and the topological susceptibility in the $\epsilon$-regime, as a function of the fermion mass. The microscopic…

High Energy Physics - Lattice · Physics 2020-01-01 Taro V. Brown , Maarten Golterman , Svend Krøjer , Yigal Shamir , K. Splittorff

A massless up quark has long been proposed as a solution to the strong CP problem. While this solution is sometimes thought to have been excluded, it is actually still ill-defined. In this work, we study the mass dependence of the physical…

High Energy Physics - Lattice · Physics 2016-11-23 Julien Frison , Ryuichiro Kitano , Norikazu Yamada

We compute the topological susceptibility $\chi_t$ of 2+1-flavor lattice QCD with dynamical M\"obius domain-wall fermions, whose residual mass is kept at 1 MeV or smaller. In our analysis, we focus on the fluctuation of the topological…

High Energy Physics - Lattice · Physics 2018-04-18 Sinya Aoki , Guido Cossu , Hidenori Fukaya , Shoji Hashimoto , Takashi Kaneko

We compute the topological susceptibility $\chi_t$ of lattice QCD with $2+1$ dynamical quark flavors described by the M\"obius domain wall fermion. Violation of chiral symmetry as measured by the residual mass is kept at $\sim$1 MeV or…

High Energy Physics - Lattice · Physics 2019-12-06 S. Aoki , G. Cossu , H. Fukaya , S. Hashimoto , T. Kaneko

We present the results on topological susceptibility and chiral observables in $N_f=2+1+1$ QCD for temperature range $120<T<600$ MeV. The lattice simulations are performed with Wilson twisted mass fermions at physical pion, strange and…

High Energy Physics - Lattice · Physics 2021-12-01 A. Yu. Kotov , M. P. Lombardo , A. Trunin

Using lattice QCD simulations with $N_f = 2$ dynamical fermions, we study the axial $U(1)$ symmetry, topological charge, and Dirac eigenvalue spectra in the high-temperature phase in which the chiral symmetry is restored. Our gauge…

High Energy Physics - Lattice · Physics 2020-07-10 Kei Suzuki , Sinya Aoki , Yasumichi Aoki , Guido Cossu , Hidenori Fukaya , Shoji Hashimoto

We present a measurement of the topological susceptibility in two flavor QCD. In this observable, large autocorrelations are present and also sizable cutoff effects have to be faced in the continuum extrapolation. Within the statistical…

High Energy Physics - Lattice · Physics 2015-06-22 Mattia Bruno , Stefan Schaefer , Rainer Sommer
‹ Prev 1 2 3 10 Next ›