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Related papers: Are Parton Distributions Positive?

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We outline an approach to calculate the transverse-momentum-dependent distribution of linearly polarized gluons inside an unpolarized hadron on the lattice with the help of large momentum effective theory. To achieve this purpose, we…

High Energy Physics - Phenomenology · Physics 2024-02-02 Shuai Zhao

In this talk, we review a QCD factorization based approach to extract parton distribution and correlation functions from lattice QCD calculation of single hadron matrix elements of quark-gluon operators. We argue that although the lattice…

High Energy Physics - Phenomenology · Physics 2015-06-23 Yan-Qing Ma , Jian-Wei Qiu

Positivity bounds for twist-two parton distributions in multicolored QCD are stronger than their analogs at finite $N_c$. They include the enhanced large $N_{c}$ version of Soffer inequality. These bounds are compatible with the DGLAP…

High Energy Physics - Phenomenology · Physics 2017-08-23 P. V. Pobylitsa

We show that the parton distribution functions (PDF) described by the statistical model have very interesting physical properties which help to understand the structure of partons. The role of the quark helicity components is emphasized as…

High Energy Physics - Phenomenology · Physics 2015-09-28 Claude Bourrely

The quantum statistical parton distributions approach proposed more than one decade ago is revisited by considering a larger set of recent and accurate Deep Inelastic Scattering experimental results. It enables us to improve the description…

High Energy Physics - Phenomenology · Physics 2015-10-22 Jacques Soffer , Claude Bourrely

We report global analysis results for polarized parton distribution functions in the nucleon. The optimum distributions are determined by using spin asymmetry data on polarized lepton scattering on proton, neutron, and deuteron. Their…

High Energy Physics - Phenomenology · Physics 2009-11-11 M. Hirai , S. Kumano , N. Saito

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 study the factorization of quasi generalized quark distributions with twist-2 generalized parton distributions. We use an approach which is different than that used in literature. Using the approach we derive the factorization relations…

High Energy Physics - Phenomenology · Physics 2022-09-07 J. P. Ma , Z. Y. Pang , G. P. Zhang

We study the evolution behavior of generalized parton distributions at small longitudinal momentum fraction. Particular attention is paid to the ratio of a generalized parton distribution and its forward limit, to the mixing between quarks…

High Energy Physics - Phenomenology · Physics 2008-11-26 Markus Diehl , Wolfgang Kugler

An updated next-to-leading order (NLO) QCD analysis of the spin asymmetries A_1^N(x,Q^2) and parton distributions delta f(x,Q^2) in longitudinally polarized deep-inelastic lepton-nucleon scattering is presented within the framework of the…

High Energy Physics - Phenomenology · Physics 2007-05-23 M. Stratmann

Parton distribution and correlation functions describe the relation between a hadron and the quarks and gluons (or collectively, the partons) within it, and carry rich information on hadron's partonic structure that cannot be calculated by…

High Energy Physics - Phenomenology · Physics 2020-01-08 Jian-Wei Qiu

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

Recently, a semiclassical approach to diffraction has been proposed, which treats the proton as a classical colour field. The present paper demonstrates that this approach is consistent with the concept of diffractive parton distributions.…

High Energy Physics - Phenomenology · Physics 2008-11-26 A. Hebecker

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

Generalized parton distributions (GPDs) are studied at the hadronic (nonperturbative) scale within different assumptions based on a relativistic constituent quark model. In particular, by means of a meson-cloud model we investigate the role…

High Energy Physics - Phenomenology · Physics 2009-11-11 S. Boffi , B. Pasquini , M. Traini

We present a study of the parton distributions in transverse position or impact parameter space using a recent parametrization of u and d quark generalized parton distributions (GPDs) $H(x,t)$ and $E(x,t)$ at zero skewness. We make a…

High Energy Physics - Phenomenology · Physics 2009-12-22 D. Chakrabarti , R. Manohar , A. Mukherjee

In the quantum statistical parton distributions approach proposed more than one decade ago to describe the parton structure, new properties are now understood, in particular, the relation between quarks and antiquarks which leads to very…

High Energy Physics - Phenomenology · Physics 2018-12-05 Claude Bourrely

A new generation of parton distribution functions with increased precision and quantitative estimates of uncertainties is presented. This work includes a full treatment of available experimental correlated systematic errors for both new and…

High Energy Physics - Phenomenology · Physics 2007-05-23 Wu-Ki Tung

We investigate the impact parameter dependent parton distributions for a relativistic composite system in light-front framework. We take an effective two-body spin-1/2 state, namely an electron dressed with a photon in QED. We express the…

High Energy Physics - Phenomenology · Physics 2009-11-10 D. Chakrabarti , A. Mukherjee

We use phenomenological nonlocal Lagrangians, which lead to non trivial forms for the quark propagator, to describe the pion. We define a procedure, based on the Dyson-Schwinger equations, for the calculation of the pion parton…

High Energy Physics - Phenomenology · Physics 2009-11-11 S. Noguera , V. Vento