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Related papers: Nucleon charges with dynamical overlap fermions

200 papers

We report lattice QCD results on the axial charges of ground and excited nucleon states of both parities. This is the first study of these quantities with approximately chiral (CI) fermions. Two energy levels in the range of the negative…

High Energy Physics - Lattice · Physics 2012-02-14 T. Maurer , T. Burch , L. Ya. Glozman , C. B. Lang , D. Mohler , A. Schäfer

The strangeness contribution to the electric and magnetic properties of the nucleon has been under investigation experimentally for many years. Lattice Quantum Chromodynamics (LQCD) gives theoretical predictions of these measurements by…

High Energy Physics - Lattice · Physics 2008-01-24 Dean Darnell

We present a numerical lattice quantum chromodynamics calculation of isovector form factors and the first few moments of the isovector structure functions of the nucleon. The calculation employs two degenerate dynamical flavors of…

High Energy Physics - Lattice · Physics 2008-12-18 Huey-Wen Lin , Tom Blum , Shigemi Ohta , Shoichi Sasaki , Takeshi Yamazaki

We present a QCD calculation of the $u$, $d$ and $s$ scalar quark contents of nucleons based on $47$ lattice ensembles with $N_f = 2+1$ dynamical sea quarks, $5$ lattice spacings down to $0.054\,\text{fm}$, lattice sizes up to…

High Energy Physics - Lattice · Physics 2016-05-12 S. Durr , Z. Fodor , C. Hoelbling , S. D. Katz , S. Krieg , L. Lellouch , T. Lippert , T. Metivet , A. Portelli , K. K. Szabo , C. Torrero , B. C. Toth , L. Varnhorst

A review of recent nucleon structure calculations within lattice QCD is presented. The nucleon excited states, the axial charge, the isovector momentum fraction and helicity distribution are discussed, assessing the methods applied for…

High Energy Physics - Lattice · Physics 2022-03-02 C. Alexandrou , M. Constantinou , V. Drach , K. Hatziyiannakou , K. Jansen , C. Kallidonis , G. Koutsou , T. Leontiou , A. Vaquero

We calculate the chiral condensate of QCD with 2, 2+1 and 3 flavors of sea quarks. Lattice QCD simulations are performed employing dynamical overlap fermions with up and down quark masses covering a range between 3 and 100 MeV. On L ~…

High Energy Physics - Lattice · Physics 2015-03-17 H. Fukaya , S. Aoki , T. W. Chiu , S. Hashimoto , T. Kaneko , J. Noaki , T. Onogi , N. Yamada

We report isovector form factors and low moments of isovector structure functions of nucleon from the coarse RIKEN-BNL-Columbia (RBC) and UKQCD joint dynamical (2+1)-flavor domain-wall fermions (DWF) ensembles. The lattice cut off is…

High Energy Physics - Lattice · Physics 2008-10-02 Shigemi Ohta , Takeshi Yamazaki

A calculational scheme for obtaining the electric polarizability of the neutron in lattice QCD with dynamical quarks is developed, using the background field approach. The scheme differs substantially from methods previously used in the…

High Energy Physics - Lattice · Physics 2008-11-26 Michael Engelhardt

I review the lattice formulations of vector-like gauge theories (e.g. QCD) with domain-wall/overlap fermions, and discuss how to optimize the chiral symmetry for any finite $ N_s $ (sites in the fifth dimension). In this formulation, quark…

High Energy Physics - Lattice · Physics 2011-02-16 Ting-Wai Chiu

Nucleon matrix elements of various four-quark operators are evaluated in quenched lattice QCD using Wilson fermions. Some of these operators give rise to twist-four contributions to nucleon structure functions. Furthermore, they bear…

High Energy Physics - Lattice · Physics 2008-11-26 M. Göckeler , R. Horsley , B. Klaus , D. Pleiter , P. E. L. Rakow , S. Schaefer , A. Schäfer , G. Schierholz

We present an analysis of the pion-nucleon $\sigma$-term, $\sigma_{\pi N}$, using six ensembles with 2+1+1-flavor highly improved staggered quark action generated by the MILC collaboration. The most serious systematic effect in lattice…

High Energy Physics - Lattice · Physics 2021-12-17 Rajan Gupta , Sungwoo Park , Martin Hoferichter , Emanuele Mereghetti , Boram Yoon , Tanmoy Bhattacharya

We compute the disconnected quark loops contributions entering the determination of nucleon observables, by using a $N_f = 2$ ensemble of twisted mass fermions with a clover term at a pion mass $m_\pi = 133$ MeV. We employ exact deflation…

We evaluate the strangeness-conserving $N N$, $\Sigma\Sigma$, $\Xi\Xi$, $\Lambda\Sigma$ and the strangeness-changing $\Lambda N$, $\Sigma N$, $\Lambda\Xi$, $\Sigma\Xi$ axial charges in lattice QCD with two flavors of dynamical quarks and…

High Energy Physics - Lattice · Physics 2010-03-02 G. Erkol , M. Oka , T. T. Takahashi

We evaluate the light, strange and charm scalar content of the nucleon using one lattice QCD ensemble generated with two degenerate light quarks with mass fixed to their physical value. We use improved techniques to evaluate the…

We present results from simulations of two flavors of dynamical overlap fermions on 8^4 lattices at three values of the sea quark mass and a lattice spacing of about 0.16 fm. We measure the topological susceptibility and the chiral…

High Energy Physics - Lattice · Physics 2009-11-11 Thomas DeGrand , Stefan Schaefer

We present recent developments in lattice QCD simulations as applied in the study of hadron structure. We discuss the challenges and perspectives in the evaluation of benchmark quantities such as the nucleon axial charge and the isovector…

High Energy Physics - Lattice · Physics 2015-06-19 Constantia Alexandrou

Using an approach free from momentum extrapolation, we calculate the nucleon magnetic moment and the fraction of the nucleon spin carried by the quark angular momentum in the quenched lattice QCD approximation. Quarks with three values of…

High Energy Physics - Lattice · Physics 2009-11-07 Valeriya Gadiyak , Xiangdong Ji , Chulwoo Jung

We present a lattice calculation of the low energy constants of QCD with $N_c=3$, 4 and 5 colors and $N_f=2$ flavors of degenerate mass fermions. We fit data for the pseudoscalar meson mass, the pseudoscalar decay constant, and the Axial…

High Energy Physics - Lattice · Physics 2023-09-22 Thomas DeGrand , Evan Wickenden

The electromagnetic form factors provide important insight into the internal structure of the nucleon and continue to be of major interest for experiment and phenomenology. For an intermediate range of momenta the form factors can be…

We study the quenched chiral behavior of hadrons with the pseudoscalar mass as low as $\approx 280$ MeV. We look for quenched chiral logs in the pion mass, determine the renormalized quark mass, and observe quenched artifacts in the $a_0$…

High Energy Physics - Lattice · Physics 2008-11-26 Shao-Jing Dong , Terrence Draper , Ivan Horvath , Frank Lee , Jianbo Zhang