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Related papers: Polarized Parton Distributiions and Light-Front Dy…

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Based on both the constituent quark picture and the instanton model for QCD vacuum, we calculate the unpolarized and polarized gluon distributions in the constituent quark and in the nucleon. Our approach consists of the two main steps. At…

High Energy Physics - Phenomenology · Physics 2016-05-04 Nikolai Kochelev , Hee-Jung Lee , Baiyang Zhang , Pengming Zhang

We review the status of our understanding of nucleon structure based on the modelling of different kinds of parton distributions. We use the concept of generalized transverse momentum dependent parton distributions and Wigner distributions,…

High Energy Physics - Phenomenology · Physics 2016-07-20 M. Burkardt , B. Pasquini

Light-Front Quantization -- Dirac's "Front Form" -- provides a physical, frame-independent formalism for hadron dynamics and structure. Observables such as structure functions, transverse momentum distributions, and distribution amplitudes…

High Energy Physics - Phenomenology · Physics 2015-12-22 Stanley J. Brodsky

We study $\rho$ meson unpolarized generalized parton distributions based on a light-front constituent quark model where the quark-antiquark-meson vertex is constructed under the symmetric loop momentum convention. The form factors and some…

High Energy Physics - Phenomenology · Physics 2017-09-06 Bao-Dong Sun , Yu-Bing Dong

Generalized parton distributions describe the distribution of partons in the transverse plane. For transversely polarized quarks and/or nucleons, these impact parameter dependent parton distributions are not axially symmetric. These…

High Energy Physics - Phenomenology · Physics 2008-11-26 Matthias Burkardt

A next-to-leading order QCD analysis of spin asymmetries and structure functions in polarized deep inelastic lepton nucleon scattering is presented within the framework of the radiative parton model. The $Q^2$-dependence of the spin…

High Energy Physics - Phenomenology · Physics 2007-05-23 W. Vogelsang

Nucleon elastic electromagnetic form factors obtained using both the three-body and quark + fully-interacting-diquark pictures of nucleon structure are employed to calculate an array of light-front transverse densities for the proton and…

High Energy Physics - Phenomenology · Physics 2026-02-23 Z. -N. Xu , Z. -Q. Yao , P. Cheng , C. D. Roberts , J. Rodriguez-Quintero , J. Segovia

We present a fit to spin asymmetries which gives polarized quark distributions. These functions are closely related to the ones given by the newest Martin, Roberts and Stirling fit for unpolarized structure functions. The integrals of…

High Energy Physics - Phenomenology · Physics 2009-10-28 Jan Bartelski , Stanisław Tatur

Using a simple picture of the constituent quark as a composite system of point-like partons, we construct the polarized parton distributions by a convolution between constituent quark momentum distributions and constituent quark structure…

High Energy Physics - Phenomenology · Physics 2011-04-15 Sergio Scopetta , Vicente Vento , Marco Traini

We compute the polarized quark distribution function of a bound nucleon. The Chiral Quark-Soliton model provides the quark and antiquark substructure of the nucleon embedded in nuclear matter. Nuclear effects cause significant modifications…

Nuclear Theory · Physics 2016-09-08 Jason R. Smith , Gerald A. Miller

The parton distribution functions (PDFs) of heavy mesons are evaluated from their light-front wave functions, which are obtained from a basis light-front quantization in the leading Fock sector representation. We consider the mass…

Nuclear Theory · Physics 2020-07-22 Jiangshan Lan , Chandan Mondal , Meijian Li , Yang Li , Shuo Tang , Xingbo Zhao , James P. Vary

Using global fits of valence u and d quark parton distributions and data on quark and nucleon form factors in the Euclidean region, we derive a light-front quark model for the nucleon structure consistent with quark counting rules.

High Energy Physics - Phenomenology · Physics 2015-03-26 Thomas Gutsche , Valery E. Lyubovitskij , Ivan Schmidt , Alfredo Vega

The alternative to the standard formulation of the quark-parton model is proposed. Our relativistically covariant approach is based on the solution of the master equations relating the structure and distribution functions, which…

High Energy Physics - Phenomenology · Physics 2007-05-23 P. Zavada

The representation of quark distribution and fragmentation functions in terms of non-local operators is combined with a simple spectator model. This allows us to estimate these functions for the nucleon and the pion ensuring correct…

High Energy Physics - Phenomenology · Physics 2009-10-30 R. Jakob , P. J. Mulders , J. Rodrigues

In the past year, polarized deep inelastic scattering experiments at CERN and SLAC have obtained structure function measurements off proton, neutron and deuteron targets at a level of precision never before achieved. The measurements can be…

High Energy Physics - Phenomenology · Physics 2010-04-06 T. Gehrmann , W. J. Stirling

We propose a phenomenological light-front wave function for hadrons with arbitrary twist-dimension (mesons, baryons and multiquark states), which gives the correct scaling behavior of structure functions (parton distributions) and form…

High Energy Physics - Phenomenology · Physics 2014-04-02 Thomas Gutsche , Valery E. Lyubovitskij , Ivan Schmidt , Alfredo Vega

We obtain the pion and the kaon parton distribution functions from the eigenstates of a light front effective Hamiltonian in the constituent quark-antiquark representation suitable for low-momentum scale applications. By taking these scales…

Nuclear Theory · Physics 2019-05-07 Jiangshan Lan , Chandan Mondal , Shaoyang Jia , Xingbo Zhao , James P. Vary

We review the present status of polarized structure functions measured in deep-inelastic scattering. We discuss the x and Q^2 dependence of the structure function g_1, and how it can be used to test perturbative QCD at next-to-leading order…

High Energy Physics - Phenomenology · Physics 2008-02-03 Stefano Forte

We discuss the structure functions and the parton distributions in the virtual photon target, both polarized and unpolarized, beyond the leading order in QCD. We study the factorization-scheme dependence of the parton distributions.

High Energy Physics - Phenomenology · Physics 2009-10-31 Ken Sasaki , Tsuneo Uematsu

We extend the QCD Parton Model analysis using a factorized nuclear structure model incorporating individual nucleons and pairs of correlated nucleons. Our analysis of high-energy data from lepton Deep-Inelastic Scattering, Drell-Yan and W/Z…