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Related papers: Factorisation schemes for proton PDFs

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Neural network algorithms have been recently applied to construct Parton Distribution Function (PDF) parametrizations which provide an alternative to standard global fitting procedures. We propose a technique based on an interactive neural…

High Energy Physics - Phenomenology · Physics 2009-04-30 J. Carnahan , H. Honkanen , S. Liuti , Y. Loitiere , P. R. Reynolds

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 recent results of the NNPDF collaboration on a full DIS analysis of Parton Distribution Functions (PDFs). Our method is based on the idea of combining a Monte Carlo sampling of the probability measure in the space of PDFs with…

High Energy Physics - Phenomenology · Physics 2008-05-21 NNPDF Collaboration , M. Ubiali , R. D. Ball , L. Del Debbio , S. Forte , A. Guffanti , J. I. Latorre , A. Piccione , J. Rojo

We present a study of the results obtained combining LO partonic matrix elements with either LO or NLO partons distributions. These are compared to the best prediction using NLO for both matrix elements and parton distributions. The aim is…

High Energy Physics - Phenomenology · Physics 2008-11-26 A. Sherstnev , R. S. Thorne

We discuss recent work on methods for incorporating nonleading QCD corrections in parton shower algorithms.

High Energy Physics - Phenomenology · Physics 2007-05-23 F. Hautmann

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

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). I present a methodology designed to determine…

High Energy Physics - Phenomenology · Physics 2024-05-16 Elie Hammou

We present a first attempt to design a quantum circuit for the determination of the parton content of the proton through the estimation of parton distribution functions (PDFs), in the context of high energy physics (HEP). The growing…

High Energy Physics - Phenomenology · Physics 2021-03-03 Adrián Pérez-Salinas , Juan Cruz-Martinez , Abdulla A. Alhajri , Stefano Carrazza

We give an overview of the current status of perturbative QCD factorization theorems in processes that involve transverse momentum dependent (TMD) parton distribution functions (PDFs) and fragmentation functions (FF). We enumerate those…

High Energy Physics - Phenomenology · Physics 2011-07-21 S. M. Aybat , T. C. Rogers

Many present lattice QCD approaches to calculate the parton distribution functions (PDFs) rely on a factorization formula or effective theory expansion of certain Euclidean matrix elements in boosted hadron states. In the quasi- and…

High Energy Physics - Phenomenology · Physics 2021-05-28 Xiang Gao , Kyle Lee , Swagato Mukherjee , Charles Shugert , Yong Zhao

We present NNPDF3.0, the first set of parton distribution functions (PDFs) determined with a methodology validated by a closure test. NNPDF3.0 uses a global dataset including HERA-II deep-inelastic inclusive cross-sections, the combined…

We study the correlation between different sets of parton distributions (PDFs). Specifically, viewing different PDF sets as distinct determinations, generally correlated, of the same underlying physical quantity, we examine the extent to…

High Energy Physics - Phenomenology · Physics 2021-12-09 Richard D. Ball , Stefano Forte , Roy Stegeman

Parton distributions in the virtual photon target are investigated in perturbative QCD up to the next-to-next-to-leading order (NNLO). In the case $\Lambda^2 \ll P^2 \ll Q^2$, where $-Q^2$ ($-P^2$) is the mass squared of the probe (target)…

High Energy Physics - Phenomenology · Physics 2009-08-05 Takahiro Ueda , Ken Sasaki , Tsuneo Uematsu

We present a determination of a set of polarized parton distributions (PDFs) of the nucleon, at next-to-leading order, from a global set of longitudinally polarized deep-inelastic scattering data: NNPDFpol1.0. The determination is based on…

High Energy Physics - Phenomenology · Physics 2013-04-01 The NNPDF Collaboration , Richard D. Ball , Stefano Forte , Alberto Guffanti , Emanuele R. Nocera , Giovanni Ridolfi , Juan Rojo

We present a detailed comparison of the most recent sets of NNLO PDFs from the ABM, CT, HERAPDF, MSTW and NNPDF collaborations. We compare parton distributions at low and high scales and parton luminosities relevant for LHC phenomenology.…

We derive a factorization theorem for Drell-Yan process at low q_T using effective field theory methods. In this theorem all the obtained quantities are gauge invariant and the special role of the soft function--and its subtraction…

High Energy Physics - Phenomenology · Physics 2015-06-03 Miguel G. Echevarria , Ahmad Idilbi , Ignazio Scimemi

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

High Energy Physics - Phenomenology · Physics 2016-08-08 Florian Lyonnet , Aleksander Kusina , Tomáš Ježo , Karol Kovařík , Fred Olness , Ingo Schienbein , Ji-Young Yu

We consider the impact that can be made on our understanding of parton distributions (PDFs) and QCD from early measurements at the LHCb experiment. The high rapidity values make the experiment uniquely suited to a detailed study of small-x…

High Energy Physics - Phenomenology · Physics 2008-08-14 R. S. Thorne , A. D. Martin , W. J. Stirling , G. Watt

Factorization scheme analysis of $F_2^{\gamma}(x,Q^2)$ in the next-to-leading order QCD is revisited. It is emphasized that the presence of the inhomogeneous term in the evolution equations for quark distribution functions of the photon…

High Energy Physics - Phenomenology · Physics 2007-05-23 Jiri Chyla

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…