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Related papers: Wilson Fermion Determinant in Lattice QCD

200 papers

We study exceptional modes of both the Wilson and the clover action in order to understand why quenched clover spectroscopy suffers so severely from exceptional configurations. We show that, in contrast to the case of the Wilson action, a…

High Energy Physics - Lattice · Physics 2015-06-25 T. DeGrand , A. Hasenfratz , T. G. Kovacs

We compute the electromagnetic form factors of the nucleon in quenched lattice QCD, using non-perturbatively improved Wilson fermions, and compare the results with phenomenology and chiral effective field theory.

High Energy Physics - Lattice · Physics 2010-04-06 M. Göckeler , T. R. Hemmert , R. Horsley , D. Pleiter , P. E. L. Rakow , A. Schäfer , G. Schierholz

We present an update on Numerical Stochastic Perturbation Theory projects for Lattice QCD, which are by now run on apeNEXT. As a first issue, we discuss a strategy to tackle finite size effects which can be quite sizeable in the computation…

High Energy Physics - Lattice · Physics 2009-04-14 Francesco Di Renzo , Luigi Scorzato , Christian Torrero

The maximally twisted lattice QCD action of an $SU_f(2)$ doublet of mass degenerate Wilson quarks gives rise to a real positive fermion determinant and it is invariant under the product of standard parity times the change of sign of the…

High Energy Physics - Lattice · Physics 2009-11-10 R. Frezzotti , G. C. Rossi

We present here the latest results from the QCDSF collaboration for (moments of) structure functions and generalized form factors in full QCD with Nf=2 O(a)-improved Wilson fermions based on simulations closer to the chiral and continuum…

High Energy Physics - Lattice · Physics 2008-11-26 M. Göckeler , P. Hägler , R. Horsley , D. Pleiter , P. E. L. Rakow , A. Schäfer , G. Schierholz , J. M. Zanotti

In a progress toward searching for the QCD critical point, we study the finite density phase transition of $N_f = 4$ and 2 lattice QCD at finite temperature with the canonical ensemble approach. We develop a winding number expansion method…

High Energy Physics - Lattice · Physics 2010-10-04 Anyi Li , Andrei Alexandru , Keh-Fei Liu , Xiangfei Meng

We present results for the b \bar b spectrum obtained using an O(M_bv^6)-correct non-relativistic lattice QCD action. Propagators are evaluated on SESAM's three sets of dynamical gauge configurations generated with two flavours of Wilson…

High Energy Physics - Lattice · Physics 2009-10-30 A. Spitz , N. Eicker , J. Fingberg , S. Güsken , H. Hoeber , Th. Lippert , K. Schilling , J. Viehoff

We calculate the equation of state of strongly coupled Hamiltonian lattice QCD at finite density by constructing a solution to the equation of motion corresponding to an effective Hamiltonian using Wilson fermions. We find that up to and…

High Energy Physics - Phenomenology · Physics 2015-06-25 Yasuo Umino

We study the implementation of the even-odd Wilson fermion matrix for lattice QCD simulations on the A64FX architecture. Efficient coding of the stencil operation is investigated for two-dimensional packing to SIMD vectors. We measure the…

Distributed, Parallel, and Cluster Computing · Computer Science 2023-03-16 Issaku Kanamori , Keigo Nitadori , Hideo Matsufuru

We present the results of our lattice QCD computation of the electric ($E_{1}$) and magnetic $(M_{2})$ form factors relevant to the $\chi_{c1}\to J/\psi\,\gamma$ decay by using the gauge field configurations produced by the Extended Twisted…

High Energy Physics - Lattice · Physics 2025-06-23 D. Bečirević , R. Di Palma , R. Frezzotti , G. Gagliardi , V. Lubicz , F. Sanfilippo , N. Tantalo

We present recent lattice results on the baryon spectrum, nucleon electromagnetic and axial form factors, nucleon to $\Delta$ transition form factors as well as the $\Delta$ electromagnetic form factors. The masses of the low lying baryons…

High Energy Physics - Lattice · Physics 2015-05-13 C. Alexandrou

The electromagnetic nucleon to Delta transition form factors are evaluated using two degenerate flavors of dynamical Wilson fermions and using dynamical sea staggered fermions with domain wall valence quarks. The two subdominant quadrupole…

High Energy Physics - Lattice · Physics 2008-11-26 C. Alexandrou , G. Koutsou , H. Neff , J. W. Negele , W. Schroers , A. Tsapalis

We use lattice simulations to study the single-site version of SU(N) lattice gauge theory with two flavors of Wilson-Dirac fermions in the adjoint representation, a theory whose large volume correspondent is expected to be conformal or…

High Energy Physics - Lattice · Physics 2013-05-30 Barak Bringoltz , Mateusz Koren , Stephen R. Sharpe

We compute the vacuum polarisation on the lattice in quenched QCD using non-perturbatively improved Wilson fermions. Above Q^2 of about 2 GeV^2 the results are very close to the predictions of perturbative QCD. Below this scale we see signs…

High Energy Physics - Lattice · Physics 2008-11-26 M. Göckeler , R. Horsley , W. Kürzinger , D. Pleiter , P. E. L. Rakow , G. Schierholz

The modelling of the ultraviolet contributions to the quark determinant in lattice QCD in terms of a small number of Wilson loops is examined. Complete Dirac spectra are obtained for sizeable ensembles of SU(3) gauge fields at $\beta$=5.7…

High Energy Physics - Lattice · Physics 2016-08-25 A. Duncan , E. Eichten , R. Roskies , H. Thacker

We present a lattice QCD calculation of the low energy constants of the leading order chiral Lagrangian. In these simulations the epsilon regime is reached by using tree-level improved nHYP Wilson fermions combined with reweighting in the…

High Energy Physics - Lattice · Physics 2008-11-26 Anna Hasenfratz , Roland Hoffmann , Stefan Schaefer

Recently, random matrix theory predictions for the distribution of low-lying Dirac operator eigenvalues have been extended to include lattice effects for both staggered and Wilson fermions. We computed low-lying eigenvalues for the…

High Energy Physics - Lattice · Physics 2011-12-09 Urs M. Heller

Extracting parton structure from lattice quantum chromodynamics (QCD) calculations requires studying the coordinate scale $z_3$ dependence of the matrix elements of bilocal operators. The most significant contribution comes from the $z_3$…

High Energy Physics - Lattice · Physics 2025-05-30 Joe Karpie , Christopher Monahan , Anatoly Radyushkin

We explore the QCD phase diagram at finite density with four-flavor staggered fermions using the complex Langevin method, which is a promising approach to overcome the sign problem. In our previous work on an $8^3 \times 16$ lattice at…

High Energy Physics - Lattice · Physics 2019-12-03 Shoichiro Tsutsui , Yuta Ito , Hideo Matsufuru , Jun Nishimura , Shinji Shimasaki , Asato Tsuchiya

The quasi-PDF approach provides a path to computing parton distribution functions (PDFs) using lattice QCD. This approach requires matrix elements of a power-divergent operator in a nucleon at high momentum and one generically expects…