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Related papers: Theoretical issues in PDF determination and associ…

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We present a comprehensive new global QCD analysis of unpolarized parton distribution functions (PDFs) based upon proton, deuteron and $A\!=\!3$ data, including the latest inclusive deep-inelastic scattering (DIS) measurements from…

High Energy Physics - Phenomenology · Physics 2026-05-04 C. Cocuzza , W. Melnitchouk , N. Sato , A. W. Thomas

We present a determination of the parton distributions of the nucleon from a global set of hard scattering data using the NNPDF methodology including heavy quark mass effects: NNPDF2.1. In comparison to the previous NNPDF2.0 parton…

Using the recently derived NNLO cross sections \cite{Czakon:2013goa}, we provide NNLO+NNLL theoretical predictions for top quark pair production based on all the available NNLO PDF sets, and compare them with the most precise LHC and…

High Energy Physics - Phenomenology · Physics 2015-06-15 Michal Czakon , Michelangelo L. Mangano , Alexander Mitov , Juan Rojo

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 a determination of the parton distributions of the nucleon from a global set of hard scattering data using the NNPDF methodology: NNPDF2.0. Experimental data include deep-inelastic scattering with the combined HERA-I dataset,…

High Energy Physics - Phenomenology · Physics 2014-11-20 Richard D. Ball , Luigi Del Debbio , Stefano Forte , Alberto Guffanti , Jose I. Latorre , Juan Rojo , Maria Ubiali

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 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

We determine the uncertainty on the strong coupling alpha_S due to the experimental errors on the data fitted in global analysis of hard-scattering data, within the standard framework of leading-twist fixed-order collinear factorisation in…

High Energy Physics - Phenomenology · Physics 2009-11-22 A. D. Martin , W. J. Stirling , R. S. Thorne , G. Watt

The presence of nuclear medium and collective phenomena which involve several nucleons modify the parton distribution functions of nuclei (nPDFs) compared to those of a free nucleon. These modifications have been investigated by different…

High Energy Physics - Phenomenology · Physics 2013-11-11 H. Honkanen , M. Strikman , V. Guzey

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

High Energy Physics - Phenomenology · Physics 2012-11-12 R. S. Thorne

We illustrate how electron Parton Distribution Functions (PDFs) with next-to-leading collinear logarithmic accuracy must be employed in the context of perturbative predictions for high-energy $e^+e^-$-collision processes. In particular, we…

High Energy Physics - Phenomenology · Physics 2022-09-23 V. Bertone , M. Cacciari , S. Frixione , G. Stagnitto , M. Zaro , X. Zhao

The full exploitation of the increasingly precise LHC measurements is essential in order to reduce the uncertainty of theoretical predictions at hadron colliders. The NNPDF2.3 fit was the first PDF determination including the effect of the…

High Energy Physics - Phenomenology · Physics 2014-07-14 Maria Ubiali

Nuclear parton distribution functions (nuclear PDFs) are non-perturbative objects that encode the partonic behaviour of bound nucleons. To avoid potential higher-twist contributions, the data probing the high-$x$ end of nuclear PDFs are…

High Energy Physics - Phenomenology · Physics 2020-06-24 Hannu Paukkunen , Pia Zurita

We study the prospects for constraining the nuclear parton distribution functions by small-x deep inelastic scattering. Performing a global fit of nuclear parton distribution functions including a sample of pseudodata representing expected…

High Energy Physics - Phenomenology · Physics 2019-08-14 Hannu Paukkunen , Kari J. Eskola , Néstor Armesto

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

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

Global analyses of Parton Distribution Functions (PDFs) have provided incisive constraints on the up and down quark components of the proton, but constraining the other flavor degrees of freedom is more challenging. Higher-order theory…

High Energy Physics - Phenomenology · Physics 2012-05-29 A. Kusina , T. Stavreva , S. Berge , F. I. Olness , I. Schienbein , K. Kovarik , T. Jezo , J. Y. Yu , K. Park

We present a systematic comparison of theoretical predictions and various high-precision experimental measurements, specifically of differential cross sections performed by the LHC run II for Drell-Yan gauge boson, top-quark pair,…

We study nuclear effects in charged current deep inelastic neutrino-iron scattering in the frame-work of a chi^2 analysis of parton distribution functions. We extract a set of iron PDFs and show that under reasonable assumptions it is…

High Energy Physics - Phenomenology · Physics 2008-11-26 I. Schienbein , J. Y. Yu , C. Keppel , J. G. Morfin , Fredrick I. Olness , J. F. Owens

Uncertainties in the parametrization of Parton Distribution Functions are a serious limiting systematic uncertainty in Large Hadron Collider searches for Beyond the Standard Model physics. This is especially true for measurements at high…

High Energy Physics - Phenomenology · Physics 2026-01-27 Yao Fu , Raymond Brock , Daniel Hayden , Chien-Peng Yuan