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200 papers

We present the first quantitative demonstration of the statistical convergence of heavy-flavor parton distribution functions at small x across modern NNLO global fits. Using the latest NNPDF4.0, CT18, and MSHT20 sets, we find a maximal…

High Energy Physics - Phenomenology · Physics 2026-01-21 S. O. Kara

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

We study the next-to-next-to-leading order (NNLO) evolution of flavour non-singlet quark densities and structure functions in massless perturbative QCD. Present information on the corresponding three-loop splitting functions is used to…

High Energy Physics - Phenomenology · Physics 2008-11-26 W. L. van Neerven , A. Vogt

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 results of our QCD analysis for nonsinglet unpolarized quark distributions and structure function $F_2(x,Q^2)$. New parameterizations are derived for the nonsinglet quark distributions for the kinematic wide range of $x$ and…

High Energy Physics - Phenomenology · Physics 2008-12-25 Ali N. Khorramian , S. Atashbar Tehrani

Sets of parton distribution functions (PDFs) of the proton are reported for the leading (LO), next-to-leading (NLO) and next-to-next-to leading order (NNLO) QCD calculations. The parton distribution functions are determined with the…

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 present MAPPDFpol1.0, a new determination of the helicity-dependent parton distribution functions (PDFs) of the proton from a set of longitudinally polarised inclusive and semi-inclusive deep-inelastic scattering data. The determination…

High Energy Physics - Phenomenology · Physics 2025-04-23 MAP , Collaboration , : , Valerio Bertone , Amedeo Chiefa , Emanuele R. Nocera

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…

We present a generalization of the $x$-space $\texttt{Candia}$ algorithm to next-to-next-to-next-to-leading order (N$^3$LO) accuracy in Quantum Chromodynamics (QCD) for solving the DGLAP evolution equations for unpolarized parton densities…

High Energy Physics - Phenomenology · Physics 2026-03-24 Casey Hampson , Marco Guzzi

We study the evolution of the flavour non-singlet deep-inelastic structure functions F_{2,NS} and F_3 at the next-to-next-to-next-to-leading order (N^3LO) of massless perturbative QCD. The present information on the corresponding three-loop…

High Energy Physics - Phenomenology · Physics 2009-11-07 W. L. van Neerven , A. Vogt

We present a new set of parton distributions obtained at NNLO. These differ from the previous sets available at NNLO due to improvements in the theoretical treatment. In particular we include a full treatment of heavy flavours in the region…

High Energy Physics - Phenomenology · Physics 2008-11-26 A. D. Martin , W. J. Stirling , R. S. Thorne , G. Watt

In this article, we review recent lattice calculations on the $x$-dependence of parton distributions, with the latter providing information on hadron structure. These calculations are based on matrix elements of boosted hadrons coupled to…

High Energy Physics - Lattice · Physics 2021-03-17 Martha Constantinou

We show how the hopping parameter expansion at order $\kappa^2$ and $\kappa^4$ can be exploited in the simulation of lattice QCD with two flavours of degenerate Wilson fermions. A natural extension of this idea is a "UV-filtering" by using…

High Energy Physics - Lattice · Physics 2018-07-04 Martin Hasenbusch

We present a new QCD analysis of parton distribution functions (PDFs) at the next-to-leading order (NLO) and next-to-next-to-leading order (NNLO). In the present paper, the role of special types of experimental measurements for extracting…

High Energy Physics - Phenomenology · Physics 2024-05-20 Majid Azizi , Ali Khorramian , Saeid Paktinat Mehdiabadi

We compute the twist-2 matching of transverse momentum dependent (TMD) helicity parton distribution and fragmentation functions at next-to-next-to-next-to-leading order (N$^3$LO) in QCD. This calculation entails the complete set of…

High Energy Physics - Phenomenology · Physics 2026-02-10 Yu Jiao Zhu

Perturbative solutions for unpolarized QED parton distribution and fragmentation functions are presented explicitly in the next-to-leading logarithmic approximation. The scheme of iterative solution of QED evolution equations is described…

High Energy Physics - Phenomenology · Physics 2023-09-06 A. B. Arbuzov , U. E. Voznaya

We present NeoPDF, an interpolation library that supports both collinear and transverse momentum-dependent parton distribution functions. NeoPDF is designed to be fast and reliable, with modern functionalities that target both current and…

High Energy Physics - Phenomenology · Physics 2025-10-07 Tanjona R. Rabemananjara

In this article, we present a Next-to-Leading Order (NLO) QCD analysis to study the role and influence of different schemes on simultaneous determination of the Parton Distribution Functions (PDFs) and strong coupling, $\alpha_s(M^2_Z)$. We…

High Energy Physics - Phenomenology · Physics 2017-09-26 A. Vafaee , A. N. Khorramian

The scale evolution of parton distributions is governed by splitting functions. We compute the four-loop splitting functions in perturbative QCD that control the evolution of quark non-singlet distributions. We confirm previous partial…

High Energy Physics - Phenomenology · Physics 2026-04-27 Thomas Gehrmann , Andreas von Manteuffel , Vasily Sotnikov , Tong-Zhi Yang