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Related papers: x-Dependent Polarized Parton Distributions

200 papers

The hard-gluonic contribution to the first moment of the polarized proton structure function $g_1^p(x)$ is dependent of the factorization convention chosen in defining the quark spin density and the hard cross section for photon-gluon…

High Energy Physics - Phenomenology · Physics 2009-10-28 Hai-Yang Cheng , Hung Hsiang Liu , Chung-Yi Wu

We review the nucleon's polarized structure functions from the viewpoint of gauge invariant, nonlocal light-cone operators in QCD. We discuss a systematic treatment of the polarized structure functions and the corresponding parton…

High Energy Physics - Phenomenology · Physics 2017-08-23 J. Kodaira

Parton branching solutions of QCD evolution equations have recently been studied to construct both collinear and transverse momentum dependent (TMD) parton distributions. In this formalism, a soft-gluon resolution scale is introduced to…

High Energy Physics - Phenomenology · Physics 2022-07-28 S. Sadeghi Barzani

Aspects of the QCD parton densities are briefly reviewed, drawing some parallels to the density matrix formulation of quantum mechanics, exemplified by Wigner functions. We elaborate on the solution of their evolution equations using…

High Energy Physics - Phenomenology · Physics 2007-05-23 Alessandro Cafarella , Claudio Coriano' , Marco Guzzi

We present a next-to-next-to-leading order (NNLO) global QCD analysis of the proton's helicity parton distribution functions (PDFs), the first of its kind. To obtain the distributions, we use data for longitudinal spin asymmetries in…

High Energy Physics - Phenomenology · Physics 2025-03-31 Ignacio Borsa , Daniel de Florian , Rodolfo Sassot , Marco Stratmann , Werner Vogelsang

In many calculations involving polarized twist-2 parton densities to higher order in the strong coupling constant one uses the Larin scheme to describe chiral effects in dimensional regularization. Upon forming observables, the scheme…

High Energy Physics - Phenomenology · Physics 2024-05-28 J. Blümlein , M. Saragnese

The complete details of our calculation of the NLO QCD corrections to heavy flavor photo- and hadroproduction with longitudinally polarized initial states are presented. The main motivation for investigating these processes is the…

High Energy Physics - Phenomenology · Physics 2007-05-23 Ingo Bojak

We consider the polarization of Lambda + Lambda-bar baryons produced in polarized Deep Inelastic Scattering at leading order, with various spin configurations: longitudinally polarized leptons and unpolarized nucleon; unpolarized leptons…

High Energy Physics - Phenomenology · Physics 2009-10-31 M. Anselmino , M. Boglione , F. Murgia

Determination of proton parton distribution functions is present under the dynamical parton model assumption by applying DGLAP equations with GLR-MQ-ZRS corrections. We provide two data sets, referred as IMParton16, which are from two…

High Energy Physics - Phenomenology · Physics 2017-04-03 Rong Wang , Xurong Chen

We investigate the behavior of spin-dependent parton distribution functions (PDFs) at large parton momentum fractions x in the context of global QCD analysis. We explore the constraints from existing deep-inelastic scattering data, and from…

High Energy Physics - Phenomenology · Physics 2015-06-19 P. Jimenez-Delgado , H. Avakian , W. Melnitchouk

We calculate large mass diphoton exclusive photoproduction in the framework of collinear QCD factorization at next to leading order in {\alpha}s and at leading twist. Collinear divergences of the coefficient function are absorbed by the…

High Energy Physics - Phenomenology · Physics 2021-08-02 Oskar Grocholski , Bernard Pire , Paweł Sznajder , Lech Szymanowski , Jakub Wagner

We investigate unpolarized and polarized gluon distributions and their applications to the Ioffe-time distributions, which are related to lattice QCD calculations of parton distribution functions. Guided by the counting rules based on the…

High Energy Physics - Phenomenology · Physics 2021-02-11 Raza Sabbir Sufian , Tianbo Liu , Arpon Paul

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

In this paper we make predictions for nondiagonal parton distributions in a proton in the LLA. We calculate the DGLAP-type evolution kernels in the LLA, solve the nondiagonal GLAP evolution equations with a modified version of the…

High Energy Physics - Phenomenology · Physics 2014-11-17 L. L. Frankfurt , A. Freund , V. Guzey , M. Strikman

I briefly review the physics of skewed parton distributions. Special emphasis is put on the relevance of target polarization, and on the different roles of small and of intermediate x_B.

High Energy Physics - Phenomenology · Physics 2007-05-23 Markus Diehl

We introduce a new family of Generalised Parton Distribution models able to fulfil by construction all the theoretical properties imposed by QCD. These models are built on standard Parton Distribution Functions and extended to off-forward…

The $\rho$ meson polarized generalized parton distribution functions, its structure functions $g_1$ and $g_2$ and its axial form factors ${\tilde G}_{1,2}$ are studied based on a light-front quark model for the first time. Comparing our…

High Energy Physics - Phenomenology · Physics 2019-02-06 Bao-Dong Sun , Yu-Bing Dong

Supposing there exists an effective charge which defines an evolution scheme for both unpolarised and polarised parton distribution functions (DFs) that is all-orders exact and using Ans\"atze for hadron-scale proton polarised valence quark…

High Energy Physics - Phenomenology · Physics 2023-08-09 Peng Cheng , Yang Yu , Hui-Yu Xing , Chen Chen , Zhu-Fang Cui , Craig D. Roberts

Based on a solution of DGLAP evolution equations at small values of Bjorken variable x, a simple analytic approximation for so-called linearly polarized gluon density \tilde{h}_1^{\perp g}(x,k_t^2, Q^2) is obtained at LO of perturbation…

High Energy Physics - Phenomenology · Physics 2023-10-13 N. A. Abdulov , X. Chen , A. V. Kotikov , A. V. Lipatov

The theoretical framework for a next-to-leading order QCD analysis of the spin-dependent parton densities Delta f^{gamma}(x,Q^2) of the longitudinally polarized photon and of its structure function g_1^{gamma}(x,Q^2) is reviewed in some…

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