Progress in top-quark pair production cross section calculations and impact on parton distribution functions of the proton

Alim Ablat; Sayipjamal Dulat; Marco Guzzi; Tie-Jiun Hou; Nikolaos Kidonakis; Ibrahim Sitiwaldi; Alberto Tonero; Keping Xie; C. -P. Yuan

arXiv · 2411.00055

Progress in top-quark pair production cross section calculations and impact on parton distribution functions of the proton

Alim Ablat·Sayipjamal Dulat·Marco Guzzi·Tie-Jiun Hou·Nikolaos Kidonakis·Ibrahim Sitiwaldi·Alberto Tonero·Keping Xie·C. -P. Yuan

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Abstract

We discuss the impact of eligible top-quark pair production differential cross-section measurements at the LHC with a collision energy of 13 TeV on the parton distribution functions (PDFs) of the proton as well as the impact of approximate next-to-next-to-next-to-leading order (aN$^3$LO) QCD corrections combined with next-to-leading order (NLO) electroweak (EW) corrections on $t\bar t$ observables. We illustrate the effects on the gluon PDF at large $x$ from an optimal baseline selection of data in NNLO global fits, and show comparisons between the theory prediction for $t\bar t$ total and differential cross sections at aN$^3$LO QCD combined with NLO EW and recent measurements from the ATLAS and CMS collaborations at the LHC.

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Alim Ablat, Sayipjamal Dulat, Marco Guzzi, Tie-Jiun Hou, Nikolaos Kidonakis, Ibrahim Sitiwaldi, Alberto Tonero, Keping Xie, C. -P. Yuan. 2024-10-30. Progress in top-quark pair production cross section calculations and impact on parton distribution functions of the proton. https://arxiv.org/abs/2411.00055

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