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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

We investigate the impact of the latest gluon parton results from lattice QCD on the global parton distribution function (PDF) analysis within the CTEQ-TEA framework. The dependence on PDF parameterization is explored using the CT18As…

High Energy Physics - Phenomenology · Physics 2025-02-18 Alim Ablat , Sayipjamal Dulat , Tie-Jiun Hou , Huey-Wen Lin , Keping Xie , C. -P. Yuan

The associated production of direct photons and heavy quarks at the LHC is presented. Predictions for the nuclear modification factor to the cross-section at ALICE are shown. It is demonstrated that this process is a great probe of the…

High Energy Physics - Phenomenology · Physics 2015-03-17 T. Stavreva

We solve for the light-front wave functions (LFWFs) of the physical photon from the eigenvectors of the light-front quantum electrodynamics (QED) Hamiltonian with the aim to determine its bare photon and electron-positron Fock components.…

High Energy Physics - Phenomenology · Physics 2022-03-09 Sreeraj Nair , Chandan Mondal , Xingbo Zhao , Asmita Mukherjee , James P. Vary

At large values of x the parton distribution functions (PDFs) of the proton are poorly constrained and there are considerable variations between different global fits. Data at such high x have already been published by the ZEUS…

High Energy Physics - Experiment · Physics 2020-07-01 ZEUS Collaboration

Double parton distribution functions (dPDFs) represent a tool to explore the 3D partonic structure of the proton. They can be measured in high energy proton-proton and proton nucleus collisions and encode information on how partons inside a…

High Energy Physics - Phenomenology · Physics 2018-04-04 Matteo Rinaldi

We include uncertainties due to missing higher order corrections to QCD computations (MHOU) used in the determination of parton distributions (PDFs) in the recent NNPDF4.0 set of PDFs. We use our previously published methodology, based on…

The strong force which binds hadrons is described by the theory of quantum chromodynamics (QCD). Determining the character and manifestations of QCD is one of the most important and challenging outstanding issues necessary for a…

High Energy Physics - Lattice · Physics 2025-06-06 Huey-Wen Lin

We present a new set of parton distributions, NNPDF3.1, which updates NNPDF3.0, the first global set of PDFs determined using a methodology validated by a closure test. The update is motivated by recent progress in methodology and available…

The strong force which binds hadrons is described by the theory of Quantum Chromodynamics (QCD). Determining the character and manifestations of QCD is one of the most important and challenging outstanding issues necessary for a…

The QCD treatment of the photon structure is recalled. Emphasis is given to the recently derived momentum sum rule, and to the proper choice of the factorization scheme and/or boundary conditions for the evolution equations beyond the…

High Energy Physics - Phenomenology · Physics 2007-05-23 Andreas Vogt

Determinations of the proton's collinear parton distribution functions (PDFs) are emerging with growing precision due to increased experimental activity at facilities like the Large Hadron Collider. While this copious information is…

High Energy Physics - Phenomenology · Physics 2019-01-24 Bo-Ting Wang , T. J. Hobbs , Sean Doyle , Jun Gao , Tie-Jiun Hou , Pavel M. Nadolsky , Fredrick I. Olness

The prospects for a measurement of nuclear parton distribution functions (PDFs) at the Large Hadron--Electron Collider are discussed in the light of recent progress made in the front of global analysis of nuclear PDFs.

High Energy Physics - Phenomenology · Physics 2019-08-12 Hannu Paukkunen

A selection of the latest and most frequently used parton distribution functions (PDFs) is incorporated in Pythia8, including the Monte Carlo-adapted PDFs from the MSTW and CTEQ collaborations. This article examines the differences in PDFs…

High Energy Physics - Phenomenology · Physics 2010-11-19 Tomas Kasemets , Torbjörn Sjöstrand

The perturbative QCD approach to quarkonium decay into a photon and hadrons is reconsidered. It is shown that a consistent treatment within perturbative QCD calls for the introduction of a fragmentation contribution which has been neglected…

High Energy Physics - Phenomenology · Physics 2009-10-28 S. Catani , F. Hautmann

We consider double parton distribution functions (dPDFs), essential quantities in double parton scattering (DPS) studies, which encode novel non perturbative insight on the partonic proton structure. We develop the formalism to extract this…

High Energy Physics - Phenomenology · Physics 2019-10-02 Matteo Rinaldi , Federico Alberto Ceccopieri

We report on the phenomenological results obtained through Dihadron Fragmentation Functions related processes. In 2015, an update on the fitting techniques for the Dihadron Fragmentation Functions has led to an improved extraction of the…

High Energy Physics - Phenomenology · Physics 2016-11-23 A. Courtoy

I review the current status of the nucleon PDFs determined from global fits with emphasis on the impact of recent experimental data and the remaining theoretical challenges.

High Energy Physics - Phenomenology · Physics 2010-12-13 S. Alekhin

We have studied the production of single isolated prompt photons in high energy proton-proton collisions at the RHIC ($\sqrt{s}$= 200 GeV) and the LHC ($\sqrt{s}$= 7 TeV) energies within the frame work of perturbative QCD upto next-to…

High Energy Physics - Phenomenology · Physics 2017-08-02 Somnath De

We examine the dependence of parton distribution functions (PDFs) on the value of the QCD coupling strength $\alpha_{s}(M_{Z})$. We explain a simple method that is rigorously valid in the quadratic approximation normally applied in PDF…

High Energy Physics - Phenomenology · Physics 2014-11-20 Hung-Liang Lai , Joey Huston , Zhao Li , Pavel Nadolsky , Jon Pumplin , Daniel Stump , C. -P. Yuan