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Related papers: A note on the QCD evolution of generalized form fa…

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Nucleon form factors at high momentum transfer |t| are treated in the framework of generalized parton distributions (GPD's). The possibility of obtaining information about parton high transverse momentum components by application of GPD's…

High Energy Physics - Phenomenology · Physics 2009-11-07 Pau Stoler

In the high energy regime, the proton structure consists of a very large number of particles called partons (quarks and gluons) that interact with each other, according to the theory of strong interactions, Quantum Chromodynamics (QCD).…

High Energy Physics - Phenomenology · Physics 2018-08-06 Gilvana C. Penedo , Werner K. Sauter

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

The generalized parton distributions are non-perturbative objects, which encode information on long distance dynamics in a number of exclusive processes. They are hybrids of conventional parton densities, distribution amplitudes and hadron…

High Energy Physics - Phenomenology · Physics 2007-05-23 A. V. Belitsky , D. Müller

We present here the latest results from the QCDSF collaboration for (moments of) structure functions and generalized form factors in full QCD with Nf=2 O(a)-improved Wilson fermions based on simulations closer to the chiral and continuum…

High Energy Physics - Lattice · Physics 2008-11-26 M. Göckeler , P. Hägler , R. Horsley , D. Pleiter , P. E. L. Rakow , A. Schäfer , G. Schierholz , J. M. Zanotti

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 revisit the evolution of generalised parton distributions (GPDs) at the leading order in the strong coupling constant $\alpha_s$ for all of the twist-2 quark and gluon operators. We rederive the relevant one-loop evolution kernels,…

High Energy Physics - Phenomenology · Physics 2024-02-16 Valerio Bertone , Rafael F. del Castillo , Miguel G. Echevarria , Óscar del Río , Simone Rodini

The extension of the method [arXiv:hep-ph/0503109] for solving the leading order evolution equation for Generalized Parton Distributions (GPDs) is presented. We obtain the solution of the evolution equation both for the flavor nonsinglet…

High Energy Physics - Phenomenology · Physics 2009-11-11 M. Kirch , A. Manashov , A. Schafer

The gravitational form factors (GFFs) of a hadron encode fundamental aspects of its structure, including its shape and size as defined from e.g., its energy density. This work presents a determination of the flavor decomposition of the GFFs…

High Energy Physics - Lattice · Physics 2024-06-25 Daniel C. Hackett , Dimitra A. Pefkou , Phiala E. Shanahan

Generalized Parton Distributions (GPDs) have emerged as a powerful framework for exploring the internal structure of hadrons in terms of their partonic constituents. Over the past three decades, the field has witnessed significant…

An approach is described to calculate Generalized Parton Distributions (GPDs) in Constituent Quark Models (CQM). The GPDs are obtained from wave functions to be evaluated in a given CQM. The general relations linking the twist-two GPDs to…

High Energy Physics - Phenomenology · Physics 2009-11-07 S. Scopetta , V. Vento

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

The new parameterization of the Generalized Parton Distributions (GPDs) t-dependence is investigated. It is shown that the new form of the GPDS allows one to reproduce sufficiently well the electromagnetic form factors of the proton and…

High Energy Physics - Phenomenology · Physics 2013-03-25 O. V. Selyugin

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

An approach is proposed to calculate Generalized Parton Distributions (GPDs) in a Constituent Quark Model (CQM) scenario. These off-diagonal distributions are obtained from momentum space wave functions to be evaluated in a given non…

High Energy Physics - Phenomenology · Physics 2007-05-23 Sergio Scopetta , Vicente Vento

Generalized parton distributions are a new type of hadronic observables which has recently stimulated great interest among theorists and experimentalists alike. Introduced to delineate the spin structure of the nucleon, the orbital angular…

High Energy Physics - Lattice · Physics 2009-11-07 Xiangdong Ji

The electromagnetic nucleon form factors provide constraints on generalized quark distributions. Key results of the study presented here are a strong dependence of the average impact parameter of quarks on their longitudinal momentum…

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

Generalized parton distributions (GPDs) have become a standard QCD tool for analyzing and parametrizing the non perturbative parton structure of hadron targets. GPDs might be viewed as non-diagonal overlaps of light-cone wave functions and…

High Energy Physics - Phenomenology · Physics 2009-02-19 B. Pasquini , S. Boffi

The parton distributions in the proton are evaluated dynamically using a nonlinear QCD evolution equation - the DGLAP equation with twist-4 (the GLR-MQ-ZSR) corrections - starting from a low scale $\mu^2$, where the nucleon consists of…

High Energy Physics - Phenomenology · Physics 2014-09-11 Xurong Chen , Jianhong Ruan , Rong Wang , Pengming Zhang , Wei Zhu

In a scenario where the constituent quarks are composite systems, Generalized Parton Distributions (GPDs) are built from wave functions to be evaluated in a Constituent Quark Model (CQM), convoluted with the GPDs of the constituent quarks…

High Energy Physics - Phenomenology · Physics 2007-05-23 Sergio Scopetta , Vicente Vento