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Abstract We study QCD corrections for the associated production of a single top quark and a photon ($$tq\gamma $$ production) at hadron colliders. We calculate the NLO cross section at LHC and future collider energies for a variety of kinematical cuts, and we estimate uncertainties from scale dependence and from parton distributions. We also calculate differential distributions in top-quark transverse-momentum and rapidity as well as photon energy. Finally, we study higher-order corrections from soft-gluon emission for this process, and we provide approximate NNLO (aNNLO) results for the cross section and top-quark differential distributions. We also compare our calculations with recent measurements from CMS and ATLAS at the LHC and find that the aNNLO corrections improve the comparison between the data and the Standard Model predictions.
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This content will become publicly available on January 3, 2026
Progress in top-quark pair production cross section calculations and impact on parton distribution functions of the proton
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 (aN3LO) QCD corrections combined with next-to-leading order (NLO) electroweak (EW) corrections on tt¯ 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 tt¯ total and differential cross sections at aN3LO QCD combined with NLO EW and recent measurements from the ATLAS and CMS collaborations at the LHC.
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- PAR ID:
- 10608051
- Publisher / Repository:
- Sissa Medialab
- Date Published:
- Page Range / eLocation ID:
- 332
- Format(s):
- Medium: X
- Location:
- Boston, USA
- Sponsoring Org:
- National Science Foundation
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