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Related papers: Generalized Parton Distributions from Lattice QCD

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Parton distribution functions (PDFs) are nonperturbative quantities describing the relation between a hadron and quarks and gluons within it. We propose to extract PDFs from QCD global analysis of "data" generated by lattice QCD…

High Energy Physics - Phenomenology · Physics 2018-10-24 Yan-Qing Ma , Jian-Wei Qiu

We present a calculation of the twist-3 generalized parton distributions (GPDs) for gluons in the proton. Our analysis is performed within a light-front constituent model where the proton is treated as a two-body state of a spin-1 gluon and…

High Energy Physics - Phenomenology · Physics 2025-10-07 Parashmani Thakuria , Madhurjya Lalung , Jayanta Kumar Sarma

We report on our exploratory study for the evaluation of the parton distribution functions from lattice QCD, based on a new method proposed in Ref.~arXiv:1305.1539. Using the example of the nucleon, we compare two different methods to…

We present an initiatory study of quark helicity flip generalized parton distributions (GPDs) in n_f=2 lattice QCD, based on clover-improved Wilson fermions for a large number of coupling constants and pion masses. Quark helicity flip GPDs…

High Energy Physics - Lattice · Physics 2008-11-26 M. Gockeler , Ph. Hagler , R. Horsley , D. Pleiter , P. E. L. Rakow , A. Schafer , G. Schierholz , J. M. Zanotti

In this work, we present the first-ever calculation of the isovector flavor combination of the twist-3 parton distribution function $g_T(x)$ for the proton from lattice QCD. We use an ensemble of gauge configurations with two degenerate…

High Energy Physics - Lattice · Physics 2020-12-30 Shohini Bhattacharya , Krzysztof Cichy , Martha Constantinou , Andreas Metz , Aurora Scapellato , Fernanda Steffens

Generalized Parton Distributions of the pion are evaluated in chiral quark models with the help of double distributions. As a result the polynomiality conditions are automatically satisfied. In addition, positivity constraints, proper…

High Energy Physics - Phenomenology · Physics 2009-11-13 Wojciech Broniowski , Enrique Ruiz Arriola , Krzysztof Golec-Biernat

Comments on the recent lattice QCD calculations of the flavor-singlet axial coupling constant $g_A^0$ and individual quark and gluon spin contributions to the proton spin is given. I point out the physics learned from these calculations as…

High Energy Physics - Lattice · Physics 2007-05-23 Keh-Fei Liu

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

The proton spin puzzle issue focused the attention on the parton spin and orbital angular momentum contributions to the proton spin. However, a complete characterization of the proton spin structure requires also the knowledge of the parton…

High Energy Physics - Phenomenology · Physics 2015-06-22 Cédric Lorcé

We determine the properties of generalised parton distributions (GPDs) from a lattice QCD calculation of the off-forward Compton amplitude (OFCA). By extending the Feynman-Hellmann relation to second-order matrix elements at off-forward…

Generalized parton distributions provide information on the longitudinal and transverse distribution of partons in the fast moving nucleon. Furthermore, they contain information on the spin structure of the nucleon. First results of a…

High Energy Physics - Phenomenology · Physics 2008-11-26 M. Göckeler , T. R. Hemmert , R. Horsley , D. Pleiter , P. E. L. Rakow , A. Schäfer , G. Schierholz , W. Schroers

We present results on the spin carried by quarks and gluons in the nucleon using lattice QCD simulations with physical values of the light, strange and charm quark masses. We also discuss selective results on the x-dependence of parton…

High Energy Physics - Lattice · Physics 2023-01-18 Constantia Alexandrou

The fully unintegrated, off-diagonal quark-quark correlator for a spin-1/2 hadron is parameterized in terms of so-called generalized parton correlation functions. Such objects, in particular, can be considered as mother distributions of…

High Energy Physics - Phenomenology · Physics 2009-08-18 S. Meissner , A. Metz , M. Schlegel

We present results for the $x$ dependence of the unpolarized, helicity, and transversity isovector quark distributions in the proton using lattice QCD, employing the method of quasi-distributions proposed by Ji in 2013. Compared to a…

High Energy Physics - Lattice · Physics 2016-09-02 Constantia Alexandrou , Krzysztof Cichy , Kyriakos Hadjiyiannakou , Karl Jansen , Fernanda Steffens , Christian Wiese

We apply the methods of Chiral Perturbation Theory to the analysis of the first moments of the Generalized Parton Distributions in a Nucleon, usually known as generalized form factors. These quantities are currently also under investigation…

High Energy Physics - Lattice · Physics 2009-04-14 Marina Dorati , Tobias A. Gail , Thomas R. Hemmert

We calculate the leading-twist helicity-dependent generalized parton distributions (GPDs) of the proton at finite skewness in the Nambu--Jona-Lasinio (NJL) model of quantum chromodynamics (QCD). From these (and previously calculated…

Nuclear Theory · Physics 2021-04-21 Adam Freese , Ian C. Cloët

We present a comprehensive study of the lowest moments of nucleon generalized parton distributions in N_f=2+1 lattice QCD using domain wall valence quarks and improved staggered sea quarks. Our investigation includes helicity dependent and…

We summarize the intuitive connection between deformations of parton distributions in impact parameter space and single-spin asymmetries. Lattice results for the $x^2$-moment of the twist-3 polarized parton distribution $g_2(x)$ are used to…

High Energy Physics - Phenomenology · Physics 2017-08-23 Matthias Burkardt

We present here the latest results from the QCDSF collaboration for moments of generalized parton distributions and transversity in two-flavour QCD, including a preliminary analysis of the pion mass dependence.

High Energy Physics - Lattice · Physics 2008-11-26 M. Gockeler , Ph. Hagler , R. Horsley , D. Pleiter , P. E. L. Rakow , A. Schafer , G. Schierholz , J. M. Zanotti

We investigate the twist-3 generalized parton distributions (GPDs) for the valence quarks of the proton within the basis light-front quantization (BLFQ) framework. We first solve for the mass spectra and light-front waved functions (LFWFs)…

High Energy Physics - Theory · Physics 2026-01-13 Ziqi Zhang , Zhi Hu , Siqi Xu , Chandan Mondal , Xingbo Zhao , James P. Vary