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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

I explain the current status of parton-distribution-function (PDF) studies and future experimental prospects on their determinations. First, unpolarized PDFs of the nucleon are introduced as a field of precision QCD physics including…

High Energy Physics - Phenomenology · Physics 2018-09-17 S. Kumano

Global perturbative QCD analyses, based on large data sets from electron-proton and hadron collider experiments, provide tight constraints on the parton distribution function (PDF) in the proton. The extension of these analyses to nuclear…

High Energy Physics - Phenomenology · Physics 2011-07-29 Paloma Quiroga-Arias , Jose Guilherme Milhano , Urs Achim Wiedemann

Parton Distribution Functions (PDFs) are a key ingredient in theoretical predictions for Large Hadron Collider (LHC) observables and play a central role in the extraction of precision Standard Model (SM) and Beyond the SM (BSM) parameters…

High Energy Physics - Phenomenology · Physics 2026-03-02 Richard D. Ball , Tommaso Giani , Felix Hekhorn , Jaco ter Hoeve , Tanjona R. Rabemananjara , Juan Rojo , Roy Stegeman , Maria Ubiali

Global perturbative QCD analyses, based on large data sets from electron-proton and hadron collider experiments, provide tight constraints on the parton distribution function (PDF) in the proton. The extension of these analyses to nuclear…

High Energy Physics - Phenomenology · Physics 2014-11-20 Paloma Quiroga-Arias , Jose Guilherme Milhano , Urs Achin Wiedemann

By working in QED, we obtain the electron, positron, and photon Parton Distribution Functions (PDFs) of the unpolarised electron at the next-to-leading logarithmic accuracy. The PDFs account for all of the universal effects of initial-state…

High Energy Physics - Phenomenology · Physics 2022-07-26 V. Bertone , M. Cacciari , S. Frixione , G. Stagnitto

We present a lattice QCD calculation of the unpolarized isovector quark parton distribution function (PDF) of the proton utilizing a perturbative matching at next-to-next-to-leading-order (NNLO). The calculations are carried out using a…

High Energy Physics - Lattice · Physics 2023-05-10 Xiang Gao , Andrew D. Hanlon , Jack Holligan , Nikhil Karthik , Swagato Mukherjee , Peter Petreczky , Sergey Syritsyn , Yong Zhao

Parton distribution functions (PDFs) describe the structure of hadrons as composed of quarks and gluons. They are needed to make predictions for short-distance processes in high-energy collisions and are determined by fitting to cross…

High Energy Physics - Phenomenology · Physics 2020-11-11 Karol Kovarik , Pavel M. Nadolsky , Davison E. Soper

We present NNPDFpol2.0, a new set of collinear helicity parton distribution functions (PDFs) of the proton based on legacy measurements of structure functions in inclusive neutral-current longitudinally polarised deep-inelastic scattering…

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

In this work, we examine the implications of electroweak corrections beyond leading order for processes of special interest in the Higgs sector. We especially explore the role of these corrections given the introduction of an explicit…

High Energy Physics - Phenomenology · Physics 2025-08-12 Amanda M. Cooper-Sarkar , Thomas Cridge , T. J. Hobbs , Joey Huston , Pavel Nadolsky , Maximiliano Ponce-Chavez , Keping Xie

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

Global perturbative QCD analyses, based on large data sets from e-p and hadron collider experiments, provide tight constraints on the parton distribution function (PDF) in the proton. The extension of these analyses to nuclear parton…

High Energy Physics - Phenomenology · Physics 2011-04-07 Paloma Quiroga-Arias , José Guilherme Milhano , Urs Achim Wiedemann

In the computation of short-distance cross sections initiated by electrons and photons one can adopt the so-called structure-function approach, in which these particles play formally the same roles as hadrons do in QCD factorisation…

High Energy Physics - Phenomenology · Physics 2020-01-08 Stefano Frixione

Beyond leading-order, perturbative QCD requires a choice of factorisation scheme to define the parton distribution functions (PDFs) and hard-process cross-section. The modified minimal-subtraction ($\overline{\mathrm{MS}}$) scheme has long…

High Energy Physics - Phenomenology · Physics 2025-05-12 Stéphane Delorme , Aleksander Kusina , Andrzej Siódmok , James Whitehead

We propose an efficacious approach to derive the generalized parton distributions for the pion and proton, based upon prior knowledge of their respective parton distribution functions (PDFs). Our method leverages on integral representations…

High Energy Physics - Phenomenology · Physics 2024-06-17 Xiaobin Wang , Zanbin Xing , Minghui Ding , Khépani Raya , Lei Chang

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 2021-07-14 Ritu Aggarwal

Parton distributions are an essential ingredient of the LHC program. PDFs are relevant for precision Standard Model measurements, for Higgs boson characterization as well as for New Physics searches. In this contribution I review recent…

High Energy Physics - Phenomenology · Physics 2013-05-16 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 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…