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Related papers: The $U_A(1)$ Problem on the Lattice

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We determine mass and flavour content of eta and eta' states using Nf=2+1+1 Wilson twisted mass lattice QCD. We describe how those flavour singlet states need to be treated in this lattice formulation. Results are presented for two values…

High Energy Physics - Lattice · Physics 2011-11-16 Konstantin Ottnad , Carsten Urbach , Chris Michael , Siebren Reker

We determine the topological susceptibility $ \chi_t $ in the trivial topological sector generated by lattice simulations of two-flavor QCD with overlap Dirac fermion, on a $16^3 \times 32$ lattice with lattice spacing $\sim$ 0.12 fm, at…

High Energy Physics - Lattice · Physics 2011-02-16 T. W. Chiu , S. Aoki , H. Fukaya , S. Hashimoto , T. H. Hsieh , T. Kaneko , H. Matsufuru , J. Noaki , K. Ogawa , T. Onogi , N. Yamada

We construct the Wess-Zumino-Witten (WZW) term in lattice gauge theory by using a Dirac operator which obeys the Ginsparg-Wilson relation. Topological properties of the WZW term known in the continuum are reproduced on the lattice as a…

High Energy Physics - Lattice · Physics 2009-11-10 Takanori Fujiwara , Kosuke Matsui , Hiroshi Suzuki , Masaru Yamamoto

Lattice QCD using fermions whose Dirac operator obeys the Ginsparg-Wilson relation, is perhaps the best known formulation of QCD with a finite cutoff. It reproduces all the low energy QCD phenomenology associated with chiral symmetry at…

High Energy Physics - Lattice · Physics 2016-08-25 Shailesh Chandrasekharan

We determine the topological susceptibility $\chi_t$ in two-flavor QCD using the lattice simulations at a fixed topological sector. The topological charge density is unambiguously defined on the lattice using the overlap-Dirac operator…

High Energy Physics - Lattice · Physics 2008-11-26 S. Aoki , T. W. Chiu , H. Fukaya , S. Hashimoto , T. H. Hsieh , T. Kaneko , H. Matsufuru , J. Noaki , K. Ogawa , T. Onogi , N. Yamada

We present an improved analysis of our lattice data for the $\eta$--$\eta'$ system, including a correction of the relevant correlation functions for residual topological finite size effects and employing consistent chiral and continuum…

High Energy Physics - Lattice · Physics 2018-03-28 Konstantin Ottnad , Carsten Urbach

We present numerical results for the 2-flavour Schwinger model with dynamical chiral lattice fermions. We insert an approximately chiral hypercube Dirac operator into the overlap formula to construct the overlap hypercube operator. This is…

High Energy Physics - Lattice · Physics 2012-04-26 Wolfgang Bietenholz , Ivan Hip , Stanislav Shcheredin , Jan Volkholz

We develop the $(1+1)$d lattice $U(1)$ gauge theory in order to define $2$-flavor massless Schwinger model, and discuss its connection with Haldane conjecture. We propose to use the central-branch Wilson fermion, which is defined by…

High Energy Physics - Lattice · Physics 2020-07-01 Tatsuhiro Misumi , Yuya Tanizaki

Based on the Ginsparg-Wilson relation, a gauge invariant formulation of electroweak SU(2)xU(1) gauge theory on the lattice is considered. If the hypercharge gauge coupling is turned off in the vacuum sector of the U(1) gauge fields, the…

High Energy Physics - Lattice · Physics 2007-05-23 Yoshio Kikukawa , Yoichi Nakayama , Hiroshi Suzuki

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

We study the overlap and the fixed point Dirac operators for massive fermions in the two-flavor lattice Schwinger model. The masses of the triplet (pion) and singlet (eta) bound states are determined down to small fermion masses and the…

High Energy Physics - Lattice · Physics 2014-11-17 Stefan Haeusler , C. B. Lang

QED_2 with mass and N flavors of fermions is constructed using Euclidean path integrals. The fermion masses are treated perturbatively and the convergence of the mass perturbation series is proven for a finite space-time cutoff. The…

High Energy Physics - Theory · Physics 2009-09-25 Christof Gattringer

We construct a 4-d lattice Dirac operator D using a systematical expansion in terms of simple operators on the lattice. The Ginsparg-Wilson equation turns into a system of coupled equations for the expansion coefficients of D. We solve…

High Energy Physics - Lattice · Physics 2010-04-06 Christof Gattringer , Ivan Hip , C. B. Lang

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

Simulations of lattice gauge theories with tensor networks and quantum computing have so far mainly focused on staggered fermions. In this paper, we use matrix product states to study Wilson fermions in the Hamiltonian formulation and…

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

The overlap Dirac operator, which satisfies the Ginsparg-Wilson relation, realizes exact chiral symmetry on the lattice without any unphysical doubler modes. To perform the path integrals, one should, however, note that the overlap fermion…

High Energy Physics - Lattice · Physics 2007-05-23 Hidenori Fukaya

We determine mass and mixing angles of eta and eta' states using Nf=2+1+1 Wilson twisted mass lattice QCD. We describe how those flavour singlet states need to be treated in this lattice formulation. Results are presented for three values…

High Energy Physics - Lattice · Physics 2019-08-13 K. Ottnad , C. Michael , S. Reker , C. Urbach

We perform numerical calculations of masses and decay constants of the lightest (flavoured) pseudoscalar, vector and axial vector mesons in the $Sp(4)$ lattice gauge theory with three Dirac fermions in the antisymmetric representation. The…

High Energy Physics - Lattice · Physics 2022-10-18 Jong-Wan Lee , Ed Bennett , Deog Ki Hong , Ho Hsiao , C. -J. David Lin , Biagio Lucini , Maurizio Piai , Davide Vadacchino

The major obstacle to a supersymmetric theory on the lattice is the failure of the Leibniz rule. We analyze this issue by using the Wess-Zumino model and a general Ginsparg-Wilson operator, which is local and free of species doublers. We…

High Energy Physics - Theory · Physics 2015-06-26 Kazuo Fujikawa

We study the 2-flavor lattice Schwinger model with Wilson fermions in the chiral limit. The quark mass is determined using the PCAC definition. We numerically compute the masses of the iso-triplet (pi) and iso-singlet particles (eta) for…

High Energy Physics - Lattice · Physics 2009-10-31 Christof Gattringer , Ivan Hip , C. B. Lang