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The role of global QCD analysis of parton distribution functions (PDFs) in collider physics at the Tevatron and LHC is surveyed. Current status of PDF analyses are reviewed, emphasizing the uncertainties and the open issues. The stability…

High Energy Physics - Phenomenology · Physics 2010-11-05 Wu-Ki Tung

We present a methodology for the construction of parton distribution functions (PDFs) designed to provide an accurate representation of PDF uncertainties for specific processes or classes of processes with a minimal number of PDF error…

High Energy Physics - Phenomenology · Physics 2016-06-17 Stefano Carrazza , Stefano Forte , Zahari Kassabov , Juan Rojo

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 discuss the impact of EW corrections on differential distributions in top-quark pair production at the LHC and future hadron colliders, focusing on the effects of initial-state photons. Performing a calculation at Next-to-Leading Order…

High Energy Physics - Phenomenology · Physics 2016-09-19 Davide Pagani , Ioannis Tsinikos , Marco Zaro

We discuss how to apply the Hessian method (i) to predict the impact of a new data set (or sets) on the parton distribution functions (PDFs) and their errors, by producing an updated best-fit PDF and error PDF sets, such as the CTEQ-TEA…

High Energy Physics - Phenomenology · Physics 2018-11-14 Carl Schmidt , Jon Pumplin , C. -P. Yuan

We complete the procedure of extracting parton distribution functions (PDFs) using large momentum effective theory (LaMET) at leading power accuracy in the hadron momentum. We derive a general factorization formula for the quasi PDFs in the…

High Energy Physics - Phenomenology · Physics 2020-11-11 Wei Wang , Jian-Hui Zhang , Shuai Zhao , Ruilin Zhu

In this proceedings we describe the computational challenges associated to the determination of parton distribution functions (PDFs). We compare the performance of the convolution of the parton distributions with matrix elements using…

High Energy Physics - Phenomenology · Physics 2019-09-25 Stefano Carrazza , Juan Cruz-Martinez , Jesús Urtasun-Elizari , Emilio Villa

Recent studies suggest that global fits of Parton Distribution Functions (PDFs) might inadvertently 'fit away' signs of new physics in the high-energy tails of the distributions measured at the high luminosity programme of the LHC (HL-LHC).…

High Energy Physics - Phenomenology · Physics 2024-10-03 Elie Hammou , Maria Ubiali

We study the sensitivity of the High-Luminosity LHC to a light baryonic dark photon B, primarily coupled to quarks, as a constituent of the proton. This is achieved by allowing for a dark photon parton distribution function (PDF) in the PDF…

High Energy Physics - Phenomenology · Physics 2022-08-24 Matthew McCullough , James Moore , Maria Ubiali

The LHC is foreseen to finally bring also the nuclear collisions to the TeV scale thereby providing new possibilities for physics studies, in particular related to the electro-weak sector of the Standard Model. We study here the Z and W…

High Energy Physics - Phenomenology · Physics 2015-03-17 Hannu Paukkunen , Carlos A. Salgado

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

The strong force which binds hadrons is described by the theory of Quantum Chromodynamics (QCD). Determining the character and manifestations of QCD is one of the most important and challenging outstanding issues necessary for a…

Knowledge of parton distribution functions (PDFs) at large momentum fraction $ x $ is not only important to study the flavor and spin dynamics of quarks in the nucleon, but also to search for signals of new physics at collider experiments.…

High Energy Physics - Phenomenology · Physics 2020-04-22 Muhammad Goharipour , S. Rostami

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…

Studying the structure of nucleons is not only important to understanding the strong interactions of quarks and gluons, but also to improving the precision of new-physics searches. Since a broad class of experiments, including the LHC and…

High Energy Physics - Lattice · Physics 2017-01-02 Huey-Wen Lin

The interpretation of LHC data, and the assessment of possible hints of new physics, require the precise knowledge of the proton structure in terms of parton distribution functions (PDFs). We present a systematic methodology designed to…

High Energy Physics - Phenomenology · Physics 2023-12-11 Elie Hammou , Zahari Kassabov , Maeve Madigan , Michelangelo L. Mangano , Luca Mantani , James Moore , Manuel Morales Alvarado , Maria Ubiali

Experiments at the LHC are collecting a wealth of data with an unprecedented level of precision. As a consequence, the theoretical error is now starting to lag behind the experimental one, and a ceaseless effort is required to reduce the…

High Energy Physics - Phenomenology · Physics 2018-10-22 Luca Rottoli

An updated analysis regarding the expected nuclear PDF constraints from the future Large Hadron Electron Collider (LHeC) experiment is presented. The new study is based on a more flexible small-$x$ parametrization which provides less biased…

High Energy Physics - Phenomenology · Physics 2016-06-30 Ilkka Helenius , Hannu Paukkunen , Nestor Armesto

In this contribution we briefly report on the progress and open problems in parton distribution functions (PDFs), with emphasis on their implications for LHC phenomenology. Then we study the impact of the recent ATLAS and CMS W lepton…

High Energy Physics - Phenomenology · Physics 2022-03-02 Juan Rojo

Electroweak corrections to hadron collider processes become relevant at the level of precision reached by present-day LHC experiments. We provide a preliminary discussion of the impact of electroweak corrections to parton distributions,…

High Energy Physics - Phenomenology · Physics 2013-11-12 Stefano Carrazza