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Related papers: Generalized Parton Distributions from Lattice QCD

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I present an extraction of generalized parton distributions from selected data on the electromagnetic nucleon form factors. The extracted distributions can in particular be used to quantify the contribution to the proton spin from the total…

High Energy Physics - Phenomenology · Physics 2013-06-26 Markus Diehl

Using the equations of motion of QCD and Lorentz invariance relations, we show a new, more direct way of obtaining the decomposition of the proton's quark transverse angular momentum into its spin and orbital components. The new…

High Energy Physics - Phenomenology · Physics 2024-10-30 Osamah Alkasassbeh , Abha Rajan , Michael Engelhardt , Simonetta Liuti

The quark orbital angular momentum component of proton spin, $L_q$, can be defined in QCD as the integral of a Wigner phase space distribution weighting the cross product of the quark's transverse position and momentum. It can also be…

High Energy Physics - Phenomenology · Physics 2016-09-07 Abha Rajan , Aurore Courtoy , Michael Engelhardt , Simonetta Liuti

We report on our exploratory study for the direct evaluation of the parton distribution functions from lattice QCD, based on a recently proposed new approach. We present encouraging results using Nf = 2 + 1 + 1 twisted mass fermions with a…

Ioffe-time distributions, which are functions of the Ioffe-time $\nu$, are the Fourier transforms of parton distribution functions with respect to the momentum fraction variable $x$. These distributions can be obtained from suitable equal…

High Energy Physics - Lattice · Physics 2018-04-18 Joseph Karpie , Kostas Orginos , Anatoly Radyushkin , Savvas Zafeiropoulos

With a special intention of clarifying the underlying spin contents of the nucleon, we investigate the generalized form factors of the nucleon, which are defined as the $n$-th $x$-moments of the generalized parton distribution functions,…

High Energy Physics - Phenomenology · Physics 2008-11-26 M. Wakamatsu , Y. Nakakoji

It is shown that, based only on two empirically known facts besides two reasonable theoretical postulates, we are inevitably led to a conclusion that the quark orbital angular momentum carries nearly half of the total nucleon spin. We also…

High Energy Physics - Phenomenology · Physics 2009-11-11 M. Wakamatsu

We analyze the moments of parton distribution functions in the pion calculated in lattice QCD, paying particular attention to their chiral extrapolation. Using the lowest three non-trivial moments calculated on the lattice, we assess the…

High Energy Physics - Lattice · Physics 2008-11-26 W. Detmold , W. Melnitchouk , A. W. Thomas

We present the first simultaneous global QCD analysis of spin-dependent parton distribution functions alongside their spin-averaged counterparts and pion, kaon, and unidentified hadron fragmentation functions. This analysis includes all…

High Energy Physics - Phenomenology · Physics 2023-09-08 C. Cocuzza , W. Melnitchouk , A. Metz , N. Sato

Parton distribution functions (DFs) have long been recognised as key measures of hadron structure. Today, theoretical prediction of such DFs is becoming possible using diverse methods for continuum and lattice analyses of strong interaction…

High Energy Physics - Phenomenology · Physics 2024-11-12 Yang Yu , Craig D. Roberts

The Generalized Parton Distributions (GPDs) are the appropriate framework for a universal description of the partonic structure of the nucleon. They characterize the dynamics of quarks and gluons inside the nucleon and consequently contain…

Nuclear Experiment · Physics 2009-08-24 E. Voutier

This talk will explain how ground state matrix elements specifying moments of quark density and spin distributions in the nucleon have been calculated in full QCD, show how physical extrapolation to the chiral limit including the physics of…

High Energy Physics - Lattice · Physics 2008-11-26 J. W. Negele

We present a Lattice QCD calculation of the second Mellin moments of the nucleon axial, vector and tensor parton distribution functions (PDFs). The calculation is performed at the physical pion mass with two different lattice spacings, and…

We extrapolate the first moments of the generalized parton distributions using heavy baryon chiral perturbation theory. The calculation is based on the one loop level with the finite range regularization. The description of the lattice data…

High Energy Physics - Phenomenology · Physics 2014-11-20 P. Wang , A. W. Thomas

We study the leading twist gluon generalized parton distributions (GPDs) and the gluon angular momentum inside the proton within a light-cone spectator model. Using the light-cone wave functions derived from the model, we provide the…

High Energy Physics - Phenomenology · Physics 2023-02-10 Chentao Tan , Zhun Lu

Parton distribution functions are key quantities for us to understand the hadronic structures in high-energy scattering, but they are difficult to calculate from lattice QCD. Recent years have seen fast development of the large-momentum…

High Energy Physics - Phenomenology · Physics 2019-04-29 Yong Zhao

This talk presents results from the QCDSF-UKQCD collaboration for moments of leading twist generalized parton distributions in two-flavor lattice QCD based on O(a) improved Wilson Fermions. We study helicity independent and helicity flip…

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 present the first global analysis of generalized parton distributions (GPDs) combing lattice quantum chromodynamics (QCD) calculations and experiment measurements including global parton distribution functions (PDFs), form factors (FFs)…

High Energy Physics - Phenomenology · Physics 2023-06-13 Yuxun Guo , Xiangdong Ji , M. Gabriel Santiago , Kyle Shiells , Jinghong Yang

Generalized parton distributions (GPDs) are among the most fundamental quantities for describing the internal structure of hadrons. In this work, we present results on isovector GPDs of the proton obtained within lattice Quantum…

The proton spin crisis remains an unsolved problem in particle physics. The spin and angular momentum of the partons inside the proton are non-perturbative quantities in QCD which cannot be calculated by using the perturbative QCD (pQCD).…

General Physics · Physics 2019-06-11 Gouranga C Nayak