English
Related papers

Related papers: Improving on the Pythia modelling of equal-scale m…

200 papers

We perform a comprehensive global QCD analysis of spin-dependent parton distribution functions (PDFs), combining all available data on inclusive and semi-inclusive deep-inelastic scattering (DIS), as well as inclusive weak boson and jet…

High Energy Physics - Phenomenology · Physics 2025-12-11 C. Cocuzza , N. T. Hunt-Smith , W. Melnitchouk , N. Sato , A. W. Thomas

Parton distribution functions (PDFs) at large $x$ are poorly constrained by high-energy experimental data, but extremely important for probing physics beyond standard model at colliders. We study the calculation of PDFs at large-$x$ through…

High Energy Physics - Phenomenology · Physics 2025-08-05 Xiangdong Ji , Yizhuang Liu , Yushan Su

We discuss a Bayesian methodology for the solution of the inverse problem underlying the determination of parton distribution functions (PDFs). In our approach, Gaussian Processes (GPs) are used to model the PDF prior, while Bayes theorem…

High Energy Physics - Phenomenology · Physics 2024-07-03 Alessandro Candido , Luigi Del Debbio , Tommaso Giani , Giacomo Petrillo

The double parton distributions (dPDF), both conventional and those corresponding to parton splitting, are calculated and compared for different two-parton combinations. The conventional and splitting dPDFs have very similar shape in $x_1$…

High Energy Physics - Phenomenology · Physics 2014-09-24 Jonathan R. Gaunt , Rafal Maciula , Antoni Szczurek

We present a first determination of the nuclear parton distribution functions (nPDF) based on the NNPDF methodology: nNNPDF1.0. This analysis is based on neutral-current deep-inelastic structure function data and is performed up to NNLO in…

High Energy Physics - Phenomenology · Physics 2019-07-23 Rabah Abdul Khalek , Jacob J. Ethier , Juan Rojo

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 distributions (DPDs) receive a short-distance contribution from a single parton splitting to yield the two observed partons. We investigate this mechanism at next-to-leading order (NLO) in perturbation theory. Technically, we…

High Energy Physics - Phenomenology · Physics 2019-08-07 Markus Diehl , Jonathan R. Gaunt , Peter Ploessl , Andreas Schafer

A set of quasi-parton distribution functions (quasi-PDFs) have been recently proposed by Ji. Defined as the matrix elements of equal-time spatial correlations, they can be computed on the lattice and should reduce to the standard PDFs when…

High Energy Physics - Phenomenology · Physics 2015-03-03 Leonard Gamberg , Zhong-Bo Kang , Ivan Vitev , Hongxi Xing

The parton distribution functions (PDFs) of the proton are one of the essential ingredients to describe physics processes at hadron colliders. The Z boson production data at the LHC have a potential to constrain PDFs, especially the gluon…

High Energy Physics - Phenomenology · Physics 2016-08-31 Rajdeep M Chatterjee , Monoranjan Guchait , Ringaile Placakyte

Parton distribution functions (PDFs) are nonperturbative quantities describing the relation between a hadron and quarks and gluons within it. We propose to extract PDFs from QCD global analysis of "data" generated by lattice QCD…

High Energy Physics - Phenomenology · Physics 2018-10-24 Yan-Qing Ma , Jian-Wei Qiu

In this paper, we present a detailed study of the unpolarized nucleon parton distribution function (PDF) employing the approach of parton pseudo-distribution functions. We perform a systematic analysis using three lattice ensembles at two…

High Energy Physics - Lattice · Physics 2020-01-29 Bálint Joó , Joseph Karpie , Kostas Orginos , Anatoly Radyushkin , David Richards , Savvas Zafeiropoulos

An extension of the xFitter open-source program for QCD analyses is presented, allowing for a polynomial parameterization of the dependence of physical observables on theoretical parameters. This extension enables simultaneous determination…

High Energy Physics - Phenomenology · Physics 2024-12-03 XiaoMin Shen , Simone Amoroso , Jun Gao , Katerina Lipka , Oleksandr Zenaiev

We show that any determination of the strong coupling $\alpha_s$ from a process which depends on parton distributions, such as hadronic processes or deep-inelastic scattering, generally does not lead to a correct result unless the parton…

High Energy Physics - Phenomenology · Physics 2020-03-18 Stefano Forte , Zahari Kassabov

We explicitly demonstrate how to correctly define the hadronic parton distributions (PDFs, TMDs, and GPDs) in the soft-wall AdS/QCD approach, based on the use of a quadratic dilaton field, providing confinement and spontaneous breaking of…

High Energy Physics - Phenomenology · Physics 2020-08-12 Valery E. Lyubovitskij , Ivan Schmidt

We derived the conditions on certain combinations of integrals of the fragmentation functions of pion using HERMES data of the sum for the charged pion multiplicities from semi-inclusive deep-inelastic scattering (SIDIS) off the deuteron…

High Energy Physics - Phenomenology · Physics 2016-03-23 Dong-Jing Yang , Fu-Jiun Jiang , Wen-Chen Chang , Chung-Wen Kao , Seung-il Nam

This paper investigates the crucial role of parton distribution functions (PDFs) in high-energy physics, particularly their impact on the extraction of generalized parton distributions (GPDs) at zero skewness. To this aim, we perform six…

High Energy Physics - Phenomenology · Physics 2026-03-23 The MMGPDs Collaboration , Fatemeh Irani , Muhammad Goharipour , K. Azizi

We apply a classical mathematical problem, the moment problem, with its related mathematical achievements, to the study of the parton distribution function (PDF) in hadron physics, and propose a strategy to sieve the moments of the PDF by…

High Energy Physics - Phenomenology · Physics 2023-10-27 Xiaobin Wang , Minghui Ding , Lei Chang

We consider the definition of a transverse-momentum-dependent parton distribution function (TMDPDF) and its evolution properties given a factorization theorem of Drell- Yan lepton pair production with a non-vanishing transverse momentum. We…

High Energy Physics - Phenomenology · Physics 2015-06-17 Miguel G. Echevarria , Ahmad Idilbi , Ignazio Scimemi

An important limitation in current fits of parton distribution functions (PDFs) is that PDF uncertainties do not include any source of theoretical uncertainty. Here we present a general method for incorporating theoretical uncertainties…

High Energy Physics - Phenomenology · Physics 2018-10-05 R. L. Pearson , C. Voisey

We develop a unified algebraic model which satisfactorily describes the internal structure of pion and kaon as well as heavy quarkonia ($\eta_c$ and $\eta_b$). For each of these mesons, we compute their generalized parton distributions…

High Energy Physics - Phenomenology · Physics 2022-08-17 L. Albino , I. M. Higuera-Angulo , K. Raya , A. Bashir