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Related papers: Parton Distributions in the Valon Model

200 papers

A discussion is presented of the manner in which uncertainties in parton distributions and related quantities are determined. One of the central problems is the criteria used to judge what variation of the parameters describing a set of…

High Energy Physics - Phenomenology · Physics 2008-11-26 R. S. Thorne , H. Boettcher , A. M. Cooper-Sarkar , B. Reisert , V. Shekelyan , W. J. Stirling , D. R. Stump , A. Vogt

Valence double parton distribution functions of the nucleon are evaluated in the framework of a simple model, where the conservation of the longitudinal momentum is taken into account. The leading-order DGLAP QCD evolution from the low…

High Energy Physics - Phenomenology · Physics 2015-06-17 Wojciech Broniowski , Enrique Ruiz Arriola

It has been suggested that parton distributions in coordinate space, so called Ioffe-time distributions, provide a more natural object for non-perturbative methods compared to the usual momentum distributions. In this paper we argue that…

High Energy Physics - Phenomenology · Physics 2009-10-28 L. Mankiewicz , T. Weigl

We briefly recall the main physical features of the parton distributions in the quantum statistical picture of the nucleon. Some predictions from a next-to-leading order QCD analysis are successfully compared to recent unpolarized and…

High Energy Physics - Phenomenology · Physics 2011-12-02 Jacques Soffer

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

Parametrization of nuclear parton distributions is investigated in the leading order of alpha_s. The parton distributions are provided at Q^2=1 GeV^2 with a number of parameters, which are determined by a chi^2 analysis of the data on…

High Energy Physics - Phenomenology · Physics 2009-11-07 M. Hirai , S. Kumano , M. Miyama

A model for the parton distributions in hadrons is derived from simple physical arguments leading to an analytical expression for the valence distributions. The sea parton distributions arise mainly from pions in hadronic fluctuations.…

High Energy Physics - Phenomenology · Physics 2007-05-23 A. Edin , G. Ingelman , K. Torokoff

We review both the counting rule and the influence of the evolution in $Q^2$ for the large $x_{Bj}$ behaviour of the valance quark distribution functions. Based on a factorization procedure we present a more general perturbative treatment…

High Energy Physics - Phenomenology · Physics 2007-05-23 D. Müller

We present an exploratory study using generalized parton distributions of several observables related to transverse degrees of freedom in hadronic structure -- the nucleon transverse momentum, the transverse radius, or impact parameter, and…

High Energy Physics - Phenomenology · Physics 2009-11-11 S. Liuti

An up-to-date global QCD analysis of high energy lepton-hadron and hadron-hadron interactions is performed to better determine the gluon and quark parton distributions in the nucleon. Improved experimental data on inclusive jet production,…

High Energy Physics - Phenomenology · Physics 2008-11-26 H. L. Lai , J. Huston , S. Kuhlmann , J. Morfin , F. Olness , J. F. Owens , J. Pumplin , W. K. Tung

In this paper polarized valon distribution is derived from unpolarized valon distribution. In driving polarized valon distribution some unknown parameters exist which must be determined by fitting to experimental data. Here we have used…

High Energy Physics - Phenomenology · Physics 2007-05-23 Ali N. Khorramian , A. Mirjalili , S. Atashbar Tehrani

Longitudinal and transverse parton distributions for pion and nucleon are calculated from hadron vertexes obtained by a study of form factors within relativistic quark models. The relevance of the one-gluon-exchange dominance at short range…

High Energy Physics - Phenomenology · Physics 2011-07-21 T. Frederico , E. Pace , B. Pasquini , G. Salmé

We give an overview of the theory for generalized parton distributions. Topics covered are their general properties and physical interpretation, the possibility to explore the three-dimensional structure of hadrons at parton level, their…

High Energy Physics - Phenomenology · Physics 2008-11-26 M. Diehl

We calculate nuclear parton distribution functions (PDFs), using the constituent quark model. We find the bounded valon distributions in a nuclear to be related to free valon distributions in a nucleon. By using improved bounded valon…

High Energy Physics - Phenomenology · Physics 2009-11-10 S. Atashbar Tehrani , Ali N. Khorramian , A. Mirjalili

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

Generalized parton distributions have been introduced in recent years as a suitable theoretical tool to study the structure of the nucleon. Unifying the concepts of parton distributions and hadronic form factors, they provide a…

High Energy Physics - Phenomenology · Physics 2011-09-30 Sigfrido Boffi , Barbara Pasquini

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…

Polarized parton distributions and structure functions of the nucleon are analyzed in the improved valon model. The valon representation provides a model to represent hadrons in terms of quarks, providing a unified description of bound…

High Energy Physics - Phenomenology · Physics 2009-11-10 Ali N. Khorramian , A. Mirjalili , S. Atashbar Tehrani

Parton distribution functions (PDFs) with QED corrections extracted from the QED$\otimes$QCD DGLAP evolution equations in the framework of "valon" model. Our results for the PDFs with QED corrections in this phenomenological model are in…

High Energy Physics - Phenomenology · Physics 2017-10-25 Marzieh Mottaghizadeh , Fatemeh Taghavi Shahri , Parvin Eslami

In these proceedings we discuss recent progress in nucleon structure using lattice QCD simulations at or near the physical value of the pion mass. Main focus will be given in observables such as the nucleon axial charge and the first…

High Energy Physics - Lattice · Physics 2017-01-12 Martha Constantinou