Top-pair production at the LHC through NNLO QCD and NLO EW
Michal Czakon,David Heymes,Alexander Mitov,Davide Pagani,Davide Pagani,Ioannis Tsinikos,Marco Zaro,Marco Zaro +7 more
TLDR
In this article, the first time predictions for top-quark pair differential distributions at the LHC at NNLO QCD accuracy and including EW corrections were presented, and the effect of the photon PDF on top-pair spectra was found to be strongly dependent on the PDF set used.Abstract:
In this work we present for the first time predictions for top-quark pair differential distributions at the LHC at NNLO QCD accuracy and including EW corrections. For the latter we include not only contributions of $$ \mathcal{O}\left({\alpha}_s^2\alpha \right) $$
, but also those of order $$ \mathcal{O}\left({\alpha}_s{\alpha}^2\right) $$
and $$ \mathcal{O}\left({\alpha}^3\right) $$
. Besides providing phenomenological predictions for all main differential distributions with stable top quarks, we also study the following issues. 1) The effect of the photon PDF on top-pair spectra: we find it to be strongly dependent on the PDF set used — especially for the top p
T
distribution. 2) The difference between the additive and multiplicative approaches for combining QCD and EW corrections: with our scale choice, we find relatively small differences between the central predictions, but reduced scale dependence within the multiplicative approach. 3) The potential effect from the radiation of heavy bosons on inclusive top-pair spectra: we find it to be, typically, negligible.read more
Citations
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New CTEQ global analysis of quantum chromodynamics with high-precision data from the LHC
Tie-Jiun Hou,Jun Gao,Timothy Hobbs,Timothy Hobbs,Keping Xie,Keping Xie,Sayipjamal Dulat,Marco Guzzi,J. Huston,Pavel Nadolsky,Jon Pumplin,Carl Schmidt,Ibrahim Sitiwaldi,Daniel R. Stump,C.-P. Yuan +14 more
TL;DR: In this article, the parton distribution functions (PDFs) from the CTEQ-TEA collaboration were obtained using a wide variety of high-precision Large Hadron Collider (LHC) data, in addition to the combined HERA I+II deep-inelastic scattering dataset, along with the datasets present in the CT14 global QCD analysis.
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The automation of next-to-leading order electroweak calculations
TL;DR: In this paper, the authors present the key features relevant to the automated computation of all the leading and next-to-leading order contributions to short-distance cross sections in a mixed-coupling expansion, with special emphasis on the first sub-leading NLO term in the QCD+EW scenario, commonly referred to as NLO EW corrections.
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A Monte Carlo global analysis of the Standard Model Effective Field Theory : the top quark sector
Nathan P. Hartland,Nathan P. Hartland,Fabio Maltoni,Fabio Maltoni,Emanuele R. Nocera,Emanuele R. Nocera,Juan Rojo,Juan Rojo,Emma Slade,Eleni Vryonidou,Cen Zhang +10 more
TL;DR: In this article, the authors present a framework for carrying out global analyses of the SMEFT at dimension-six, based on the Monte Carlo replica method for deriving a faithful estimate of the experimental and theoretical uncertainties.
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Parton distributions from LHC, HERA, Tevatron and fixed target data: MSHT20 PDFs
TL;DR: The MSHT20 set of parton distribution functions (PDFs) of the proton, determined from global analyses of the available hard scattering data, were made available at NNLO, NLO, and LO.
Journal ArticleDOI
Illuminating the photon content of the proton within a global PDF analysis
TL;DR: In this paper, the photon content of the proton is determined within a global analysis supplemented by the LUXqed constraint relating the photon PDF to lepton-proton scattering structure functions.
References
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