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Related papers: Some numerical studies of the evolution of general…

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Starting with the interpretation of parton evolution with rapidity as a branching-diffusion process, we describe the different kinds of fluctuations of the density of partons which affect the properties of QCD scattering amplitudes at…

High Energy Physics - Phenomenology · Physics 2014-09-16 A. H. Mueller , S. Munier

The quark generalised parton distributions of the pion are calculated from lightcone wavefunctions in transverse lattice gauge theory at large N_c. The pion effective size is found to decrease with increasing momentum transfer. An analytic…

High Energy Physics - Phenomenology · Physics 2009-11-10 S. Dalley

For the generalized parton distribution (GPD) E, extracted from hard exclusive processes and the Pauli form factor of the nucleon, the second moments for quarks and gluons at $t=0$ are calculated and their scale dependence analyzed. The…

High Energy Physics - Phenomenology · Physics 2025-01-03 Peter Kroll

We study the transverse momentum dependent (TMD) parton distributions at small-x in a consistent framework that takes into account the TMD evolution and small-x evolution simultaneously. The small-x evolution effects are included by…

High Energy Physics - Phenomenology · Physics 2017-06-28 Bo-Wen Xiao , Feng Yuan , Jian Zhou

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

This contribution to CIPANP 2012 highlights what we have learned about the asymmetric parton distributions of the nucleon over the past 20 years. These distributions include the transverse momentum dependent parton distributions describing…

High Energy Physics - Phenomenology · Physics 2015-06-11 Daniel Boer

We solve a unified integral equation to obtain the $x, Q_T$ and $Q$ dependence of the gluon distribution of a proton in the small $x$ regime; where $x$ and $Q_T$ are the longitudinal momentum fraction and the transverse momentum of the…

High Energy Physics - Phenomenology · Physics 2014-11-17 J. Kwiecinski , A. D. Martin , P. J. Sutton

We suggest a duality between the standard (dynamical) and statistical distributions of partons in the nucleons. The temperature parameter entering into the statistical form for the quark distributions is estimated. It is found that this…

High Energy Physics - Phenomenology · Physics 2015-05-27 J. Cleymans , G. I. Lykasov , A. S. Sorin , O. V. Teryaev

I present a highly efficient method for evolving parton distributions in perturbative QCD. The method allows evolving the parton distribution functions according to any of the commonly-used truncations of the evolution equations (which…

High Energy Physics - Phenomenology · Physics 2014-11-17 David A. Kosower

We solve for the gluon generalized parton distributions (GPDs) inside the proton, focusing specifically on leading twist chiral-even GPDs. We obtain and employ the light-front wavefunctions (LFWFs) of the proton from a light-front quantized…

High Energy Physics - Phenomenology · Physics 2023-08-17 Bolang Lin , Sreeraj Nair , Siqi Xu , Zhi Hu , Chandan Mondal , Xingbo Zhao , James P. Vary

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

We examine the QCD evolution of the helicity and transversity parton distribution functions when including also their dependence on transverse momentum. Using an appropriate definition of these polarized transverse momentum distributions…

High Energy Physics - Phenomenology · Physics 2015-06-15 Alessandro Bacchetta , Alexei Prokudin

The current status of global QCD analysis of parton distribution functions of the nucleon is reviewed. Recent progress made in determining various features of the parton structure of the nucleon, as well as outstanding open questions are…

High Energy Physics - Phenomenology · Physics 2009-09-29 Wu-Ki Tung

The Dirac and Pauli form factors of the proton and neutron are obtained in the framework of the generalized parton distributions (GPDs) with some simple momentum transfer dependence. It is shown that both sets of the existing experimental…

High Energy Physics - Phenomenology · Physics 2007-12-24 O. V. Selyugin , O. V. Teryaev

In this talk, we summarize how QCD evolution can be exploited to improve the treatment of transverse momentum dependent (TMD) parton distribution and fragmentation functions. The methods allow existing non-perturbative fits to be turned…

High Energy Physics - Phenomenology · Physics 2011-10-28 S. Mert Aybat , Ted C. Rogers

This work presents the first calculation in lattice QCD of three moments of spin-averaged and spin-polarized generalized parton distributions in the proton. It is shown that the slope of the associated generalized form factors decreases…

High Energy Physics - Lattice · Physics 2012-08-27 LHPC , SESAM Collaborations , : , Ph. Hagler , J. W. Negele , D. B. Renner , W. Schroers , Th. Lippert , K. Schilling

We introduce gauge-invariant quark and gluon angular momentum distributions after making a generalization of the angular momentum density operators. From the quark angular momentum distribution, we define the gauge-invariant and…

High Energy Physics - Phenomenology · Physics 2009-10-31 Pervez Hoodbhoy , Xiangdong Ji , Wei Lu

An updated flexible parametrization of the generalized parton distributions in the quark, antiquark and gluon sectors is presented using constraints from high precision electron nucleon deep inelastic scattering data, as well as from the…

High Energy Physics - Phenomenology · Physics 2025-11-06 Zaki Panjsheeri , Douglas Q. Adams , Adil Khawaja , Saraswati Pandey , Kemal Tezgin , Simonetta Liuti

In the present study, we explore the properties of generalized parton distributions (GPDs) for the kaon and pion within the framework of the nonlocal chiral quark model (NL$\chi$QM). Valence quark GPDs of the kaon and pion are analyzed with…

High Energy Physics - Phenomenology · Physics 2025-03-28 Hyeon-Dong Son , Parada T. P. Hutauruk

We study the QCD evolution for the twist-three quark-gluon correlation functions associated with the transverse momentum odd quark distributions. Different from that for the leading twist quark distributions, these evolution equations…

High Energy Physics - Phenomenology · Physics 2009-07-09 Jian Zhou , Feng Yuan , Zuo-Tang Liang