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Related papers: The photon PDF within the CT18 global analysis

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We present new parton distribution functions (PDFs) up to next-to-next-to-leading order (NNLO) from the CTEQ-TEA global analysis of quantum chromodynamics. These differ from previous CT PDFs in several respects, including the use of data…

High Energy Physics - Phenomenology · Physics 2016-03-09 Sayipjamal Dulat , Tie Jiun Hou , Jun Gao , Marco Guzzi , Joey Huston , Pavel Nadolsky , Jon Pumplin , Carl Schmidt , Daniel Stump , C. P. Yuan

The prospects of measuring a single-differential dijet cross section during the proposed short proton-oxygen data taking at LHC Run 3 are studied using next-to-leading-order perturbative QCD predictions. With reasonable experimental cuts…

High Energy Physics - Phenomenology · Physics 2022-03-02 Petja Paakkinen

New hard-scattering measurements from the LHC proton-lead run have the potential to provide important constraints on the nuclear parton distributions and thus contributing to a better understanding of the initial state in heavy ion…

High Energy Physics - Phenomenology · Physics 2015-06-17 Nestor Armesto , Juan Rojo , Carlos A. Salgado , Pia Zurita

In this paper we discuss the effect of the complete leading-order QED corrections to the DGLAP equations in the perturbative evolution of parton distribution functions (PDFs). This requires the extension of the purely QCD DGLAP evolution,…

High Energy Physics - Phenomenology · Physics 2016-01-27 Valerio Bertone , Stefano Carrazza , Davide Pagani , Marco Zaro

We review progress in the global QCD analysis by the CTEQ-TEA group since the publication of CT18 parton distribution functions (PDFs) in the proton. Specifically, we discuss comparisons of CT18 NNLO predictions with the LHC 13 TeV…

Direct photon production in hadronic collisions provides a handle on the gluon PDF by means of the QCD Compton scattering process. In this work we revisit the impact of direct photon production on a global PDF analysis, motivated by the…

High Energy Physics - Phenomenology · Physics 2018-06-12 John M. Campbell , Juan Rojo , Emma Slade , Ciaran Williams

We present a new set of parton distribution functions (PDFs) based on a fully global dataset and machine learning techniques: NNPDF4.0. We expand the NNPDF3.1 determination with 44 new datasets, mostly from the LHC. We derive a novel…

In the framework of quantum chromodynamics (QCD), parton distribution functions (PDFs) quantify how the momentum and spin of a hadron are divided among its quark and gluon constituents. Two main approaches exist to determine PDFs. The first…

The xFitter project (former HERAFitter project) is an open-source package that provides a framework for the determination of the parton distribution functions (PDFs) of the proton for many different kinds of analyses in Quantum…

High Energy Physics - Phenomenology · Physics 2017-09-06 Francesco Giuli

The prompt photon production in hadronic collisions has a long history of providing information on the substructure of hadrons and testing the perturbative techniques of QCD. Some valuable information about the parton densities in the…

High Energy Physics - Phenomenology · Physics 2017-03-14 Muhammad Goharipour , Hossein Mehraban

We present an updated global analysis of collinearly factorized nuclear parton distribution functions (PDFs) at next-to-leading order in perturbative QCD. In comparison to our previous fit, EPPS16, the present analysis includes more data…

High Energy Physics - Phenomenology · Physics 2022-05-25 Kari J. Eskola , Petja Paakkinen , Hannu Paukkunen , Carlos A. Salgado

I review recent progress in the NNPDF global analyses of parton distributions (PDFs) focusing on developments contributing to its new upcoming release: NNPDF4.0. The NNPDF4.0 determination represents unprecedented progress in three main…

High Energy Physics - Phenomenology · Physics 2021-04-20 Juan Rojo

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

We present the new CTEQ-TEA global analysis of quantum chromodynamics (QCD). In this analysis, parton distribution functions (PDFs) of the nucleon are determined within the Hessian method at the next-to-next-to-leading order (NNLO) in…

We discuss the implications of the preliminary CMS dijet data from 5.02 TeV pp and pPb collisions for gluon PDFs of the proton and nuclei. The preliminary pp data show a discrepancy with NLO predictions using for example the CT14 PDFs. We…

High Energy Physics - Phenomenology · Physics 2018-06-22 Kari J. Eskola , Petja Paakkinen , Hannu Paukkunen

We present the first unbiased determination of parton distribution functions (PDFs) with electroweak corrections. The aim of this thesis is to provide an exhaustive description of the theoretical framework and the technical implementation…

High Energy Physics - Phenomenology · Physics 2015-09-03 Stefano Carrazza

We present an updated determination of nuclear parton distributions (nPDFs) from a global NLO QCD analysis of hard processes in fixed-target lepton-nucleus and proton-nucleus together with collider proton-nucleus experiments. In addition to…

High Energy Physics - Phenomenology · Physics 2022-05-27 Rabah Abdul Khalek , Rhorry Gauld , Tommaso Giani , Emanuele R. Nocera , Tanjona R. Rabemananjara , Juan Rojo

In this article we present a review of the structure of the proton and the current status of our knowledge of the parton distribution functions (PDFs). The lepton-nucleon scattering experiments which provide the main constraints in PDF…

High Energy Physics - Experiment · Physics 2013-03-20 Emmanuelle Perez , Eram Rizvi

Since its start of data taking, the LHC has provided an impressive wealth of information on the quark and gluon structure of the proton. Indeed, modern global analyses of parton distribution functions (PDFs) include a wide range of LHC…

High Energy Physics - Phenomenology · Physics 2018-12-05 Rabah Abdul Khalek , Shaun Bailey , Jun Gao , Lucian Harland-Lang , Juan Rojo

We present LO, NLO and NNLO sets of parton distribution functions (PDFs) of the proton determined from global analyses of the available hard scattering data. These MMHT2014 PDFs supersede the `MSTW2008' parton sets, but are obtained within…

High Energy Physics - Phenomenology · Physics 2015-06-11 L. A. Harland-Lang , A. D. Martin , P. Motylinski , R. S. Thorne