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Related papers: The Path to N$^3$LO Parton Distributions

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In these proceedings, we reiterate and extend the discussion of the Next-to-Leading Order (NLO) QCD analysis of the charged pion Parton Distribution Function (PDF) obtained within the Fant\^omas4QCD framework. The goal of the Fant\^omas…

High Energy Physics - Phenomenology · Physics 2024-08-06 Aurore Courtoy , Lucas Kotz , Pavel Nadolsky , Fred Olness , Maximiliano Ponce-Chavez

To obtain more precise parton distribution functions (PDFs) it is important to include data on inclusive high transverse energy jet production in the global parton analyses. These data have high statistics and the NNLO terms in the…

High Energy Physics - Phenomenology · Physics 2017-04-26 A. D. Martin , M. G. Ryskin

Parton distribution functions (PDFs) play a central role in calculations for the Large Hadron Collider (LHC). To gain a deeper understanding of the emergence and interplay of constraints on the PDFs in the global QCD analyses, it is…

We discuss the determination of the parton substructure of hadrons by casting it as a peculiar form of pattern recognition problem in which the pattern is a probability distribution, and we present the way this problem has been tackled and…

High Energy Physics - Phenomenology · Physics 2020-08-31 Stefano Forte , Stefano Carrazza

In this contribution we present a status report on the recent progress towards an analysis of nuclear parton distribution functions (nPDFs) using the NNPDF methodology. We discuss how the NNPDF fitting approach can be extended to account…

High Energy Physics - Phenomenology · Physics 2018-11-15 Rabah Abdul Khalek , Jacob J. Ethier , Juan Rojo

We calculate the electron structure functions, aka parton distribution functions (PDFs), to NNLO in QED. The calculation is based on the definition of the PDFs in terms of operator matrix elements in soft collinear effective theory (SCET)…

High Energy Physics - Phenomenology · Physics 2025-12-01 Maximilian Stahlhofen

We present a model-independent determination of the nuclear parton distribution functions (nPDFs) using machine learning methods and Monte Carlo techniques based on the NNPDF framework. The neutral-current deep-inelastic nuclear structure…

High Energy Physics - Phenomenology · Physics 2020-10-28 Rabah Abdul Khalek , Jacob J. Ethier , Juan Rojo , Gijs van Weelden

We present the first complete next-to-next-to-leading order (NNLO) QCD predictions for differential distributions in the top-quark pair production process at the LHC. Our results are derived from a fully differential partonic Monte Carlo…

High Energy Physics - Phenomenology · Physics 2016-03-17 Michal Czakon , David Heymes , Alexander Mitov

We present the first next-to-next-to-next-to-leading order (N$^3$LO) calculation of the twist-2 matching coefficients for transverse momentum dependent (TMD) quark transversity parton distribution and fragmentation functions in QCD. This…

High Energy Physics - Phenomenology · Physics 2026-02-03 Yu Jiao Zhu

I consider variations in the definition of a General-Mass Variable Flavour Number Scheme (GM-VFNS) for heavy flavour structure functions, both at next-to-leading order (NLO) and at next-to-next-to leading order (NNLO). I also define a new…

High Energy Physics - Phenomenology · Physics 2010-11-19 R. S. Thorne

We carry out next-to-leading order (NLO) parton model calculations for the standard hard ``QCD'' processes in the massless Schwinger model. The asymptotic expansion of the exact result for the deep inelastic cross section is used to infer…

High Energy Physics - Phenomenology · Physics 2009-10-28 Jin Dai , James Hughes , Jun Liu

We review the current status of Parton Distribution Function (PDF) determinations for unpolarized and longitudinally polarized protons and for unpolarized nuclei, which are probed by high-energy hadronic scattering in perturbative Quantum…

High Energy Physics - Phenomenology · Physics 2020-02-18 Jacob J. Ethier , Emanuele R. Nocera

Novel PDFs taking into account resummation-improved matrix elements, albeit only in the fit of a reduced data set, allow for consistent NLO+NLL calculations of slepton pair production at the LHC. We apply a factorisation method to this…

High Energy Physics - Phenomenology · Physics 2018-04-18 J. Fiaschi , M. Klasen

Parton Distribution Functions (PDFs) contribute significantly to the uncertainty on the determination of the top-quark pole mass and other precision measurements at the Large Hadron Collider (LHC). It is crucial to understand these…

High Energy Physics - Phenomenology · Physics 2024-01-25 Jason P. Gombas , Reinhard Schwienhorst , Binbin Dong , Jarrett Fein

The forward-backward asymmetry of the Drell-Yan process in dilepton decays at high invariant masses can be used to probe the parton distribution functions at large x. The behavior of three modern PDF sets (CT18NNLO, MSHT20, and NNPDF4.0)…

High Energy Physics - Phenomenology · Physics 2023-08-02 Yao Fu , Raymond Brock , Daniel Hayden , Chien-Peng Yuan

Perturbative quantum chromodynamics (QCD) ceases to be applicable at low interaction energies due to the rapid increase of the strong coupling. In that limit, the non-perturbative regime determines the properties of quarks and gluons…

High Energy Physics - Phenomenology · Physics 2021-10-06 Rabah Abdul Khalek

In global QCD fits of parton distribution functions (PDFs), a large part of the estimated uncertainty on the PDFs originates from the choices of parametric functional forms and fitting methodology. We argue that these types of uncertainties…

High Energy Physics - Phenomenology · Physics 2023-02-21 Aurore Courtoy , Joey Huston , Pavel Nadolsky , Keping Xie , Mengshi Yan , C. -P. Yuan

Heavy quark parton distribution functions (PDFs) play an important role in several Standard Model and New Physics processes. Most PDF analyses rely on the assumption that the charm and bottom PDFs are generated perturbatively by gluon…

High Energy Physics - Phenomenology · Physics 2016-08-17 A. Kusina

Predictions of fiducial cross sections, differential cross sections and lepton charge asymmetry are presented for the production of $W^{\pm}$ bosons with leptonic decay up to next-to-next-to-leading order (NNLO) in perturbative QCD.…

High Energy Physics - Phenomenology · Physics 2016-07-26 Hasan Ogul , Kamuran Dilsiz , Emrah Tiras , Ping Tan , Yasar Onel , Jane Nachtman

We compute the next-to-next-to-leading order (NNLO) contributions to the three splitting functions governing the evolution of unpolarized non-singlet combinations of quark densities in perturbative QCD. Our results agree with all partial…

High Energy Physics - Phenomenology · Physics 2008-11-26 S. Moch , J. A. M. Vermaseren , A. Vogt