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Related papers: Nucleon axial structure from lattice QCD

200 papers

We report on a lattice QCD calculation of the nucleon axial charge, $g_A$, using M\"{o}bius Domain-Wall fermions solved on the dynamical $N_f=2+1+1$ HISQ ensembles after they are smeared using the gradient-flow algorithm. The calculation is…

We present a lattice QCD calculation of the double-virtual neutral pion transition form factor, with the goal to cover the kinematic range relevant to hadronic light-by-light scattering in the muon $g-2$. Several improvements have been made…

High Energy Physics - Lattice · Physics 2019-09-26 Antoine Gérardin , Harvey B. Meyer , Andreas Nyffeler

We present results on the nucleon electromagnetic form factors from Lattice QCD at momentum transfer up to about $12$~GeV$^2$. We analyze two gauge ensembles with the Wilson-clover fermion action, a lattice spacing of $a\approx 0.09$~fm and…

High Energy Physics - Lattice · Physics 2018-10-11 Christos Kallidonis , Sergey Syritsyn , Michael Engelhardt , Jeremy Green , Stefan Meinel , John Negele , Andrew Pochinsky

We employ a novel method to analyze Euclidean correlation functions entering the calculation of hadron energies in lattice QCD. The method is based on the sampling of all possible solutions allowed by the spectral decomposition of the…

High Energy Physics - Lattice · Physics 2015-06-23 C. Alexandrou , T. Leontiou , C. N. Papanicolas , E. Stiliaris

We calculate the electromagnetic, axial and pseudo-scalar form factors of the Nucleon to $\Delta(1232)$ transition using two dynamical light degenerate quarks and a dynamical strange quark simulated with the domain wall fermion action.…

High Energy Physics - Lattice · Physics 2011-02-25 C. Alexandrou , G. Koutsou , J. W. Negele , Y. Proestos , A. Tsapalis

We present results on the lower moments of the nucleon generalized parton distri butions within lattice QCD using two dynamical flavors of degenerate twisted mass fermions. Our simulations are performed on lattices with three different…

High Energy Physics - Lattice · Physics 2011-07-05 C. Alexandrou , J. Carbonell , M. Constantinou , P. A. Harraud , P. Guichon , K. Jansen , C. Kallidonis , T. Korzec , M. Papinutto

We determine generalized form factors of the nucleon from lattice simulations with $N_f = 2$ mass-degenerate non-perturbatively improved Wilson-Sheikholeslami-Wohlert fermions down to a pion mass of 150 MeV. We also present the resulting…

High Energy Physics - Lattice · Physics 2016-01-20 Gunnar Bali , Sara Collins , Meinulf Göckeler , Rudolf Rödl , Andreas Schäfer , Andre Sternbeck

State-of-the-art lattice QCD simulations enable the evaluation of nucleon form factors and Mellin moments with controlled systematics, yielding results with unprecedented accuracy. At the same time, new theoretical approaches are allowing…

High Energy Physics - Lattice · Physics 2024-01-30 Constantia Alexandrou , Simone Bacchio

We present new parameterizations of vector and axial nucleon form factors. We maintain an excellent descriptions of the form factors at low momentum transfers ($Q^2$), where the spatial structure of the nucleon is important, and use the…

High Energy Physics - Experiment · Physics 2008-11-26 A. Bodek , S. Avvakumov , R. Bradford , H. Budd

We present the first exploratory lattice quantum chromodynamics (QCD) calculation of the polarized gluon Ioffe-time pseudo-distribution in the nucleon. The Ioffe-time pseudo-distribution provides a frame-independent and gauge-invariant…

We describe the present status of the pion distribution amplitude (DA) as it originates from several sources: (i) a nonperturbative approach based on QCD sum rules with nonlocal condensates, (ii) an $O(\alpha_s)$ QCD analysis of the CLEO…

High Energy Physics - Phenomenology · Physics 2009-04-17 A. P. Bakulev , S. V. Mikhailov , A. V. Pimikov , N. G. Stefanis

We compute the axial and pseudoscalar form factors of the nucleon in the Dyson-Schwinger approach. To this end, we solve a covariant three-body Faddeev equation for the nucleon wave function and determine the matrix elements of the…

High Energy Physics - Phenomenology · Physics 2015-06-03 Gernot Eichmann , Christian S. Fischer

Strong isospin breaking in the spectrum of the nucleons and deltas can be studied in lattice QCD with the help of chiral perturbation theory. At leading order in the chiral expansion, the mass splittings between the proton and neutron and…

High Energy Physics - Lattice · Physics 2015-06-25 Brian C. Tiburzi , Andre Walker-Loud

A non-zero signal $A_\gamma^\mathrm{np}=(-3.0\pm1.4\pm0.2)\times 10^{-8}$ of the gamma-ray asymmetry in the neutron-proton capture was recently reported by the NPDGamma Collaboration which provides the first determination of the $\Delta…

Nuclear Theory · Physics 2019-01-18 Feng-Kun Guo , Chien-Yeah Seng

We present isovector nucleon observables: the axial, tensor, and scalar charges and the Dirac radius. Using the BMW clover-improved Wilson action and pion masses as low as 149 MeV, we achieve good control over chiral extrapolation to the…

High Energy Physics - Lattice · Physics 2013-01-11 Jeremy Green , Michael Engelhardt , Stefan Krieg , John Negele , Andrew Pochinsky , Sergey Syritsyn

We investigate the dependence of polarisation observables in elastic deuteron Compton scattering below the pion production threshold on the spin-independent and spin-dependent iso-scalar dipole polarisabilities of the nucleon. The…

Nuclear Theory · Physics 2012-03-28 Harald W. Griesshammer , Deepshikha Shukla

Very recently, a lattice QCD collaboration has explored threshold pion electroproduction near the physical pion mass and has simulated the relevant multipole amplitudes. Different multipole amplitudes are usually entangled in experimental…

High Energy Physics - Phenomenology · Physics 2026-03-09 Yu Zhuge , Zhan-Wei Liu , Derek B. Leinweber , Anthony W. Thomas

In this work, we investigate the time-like pion form factor from lattice QCD in the isosymmetric limit, a quantity that plays an important role in understanding hadron physics with substantial phenomenological applications. This observable…

High Energy Physics - Lattice · Physics 2026-03-05 Gabriele Morandi , Mattia Bruno , Francesca Argia Bresciani , Christoph Lehner , Julian Parrino

This is a review of progress in hadron structure physics from lattice QCD. Recent results on the structure of the nucleon and the pion in terms of (transition) form factors, moments of distribution amplitudes and (generalized) parton…

High Energy Physics - Lattice · Physics 2008-11-26 Philipp Hägler

We calculate the imaginary part of the induced pseudoscalar form factor of the nucleon $G_P(t)$ in the framework of two-loop heavy baryon chiral perturbation theory. The effect of the calculated three-pion continuum on the pseudoscalar…

Nuclear Theory · Physics 2009-11-10 N. Kaiser