https://doi.org/10.1140/epjc/s10052-024-12731-8
Regular Article - Theoretical Physics
Photons in the proton: implications for the LHC
1
The Higgs Centre for Theoretical Physics, University of Edinburgh, JCMB, KB, Mayfield Rd, EH9 3JZ, Edinburgh, Scotland
2
Tif Lab, Dipartimento di Fisica, Università di Milano and INFN, Sezione di Milano, Via Celoria 16, 20133, Milan, Italy
3
CERN, Theoretical Physics Department, 1211, Geneva 23, Switzerland
4
Department of Physics and Astronomy, Vrije Universiteit, 1081 HV, Amsterdam, Netherlands
5
Nikhef Theory Group, Science Park 105, 1098 XG, Amsterdam, The Netherlands
6
Department of Physics, University of Jyvaskyla, P.O. Box 35, 40014, Jyvaskyla, Finland
7
Helsinki Institute of Physics, University of Helsinki, P.O. Box 64, 00014, Helsinki, Finland
8
DAMTP, University of Cambridge, Wilberforce Road, CB3 0WA, Cambridge, UK
9
Dipartimento di Fisica, Università degli Studi di Torino and INFN, Sezione di Torino, Via Pietro Giuria 1, 10125, Turin, Italy
10
Institut für Theoretische Physik und Astrophysik, Universität Würzburg, 97074, Würzburg, Germany
Received:
18
January
2024
Accepted:
28
March
2024
Published online:
28
May
2024
We construct a set of parton distribution functions (PDFs), based on the recent NNPDF4.0 PDF set, that also include a photon PDF. The photon PDF is constructed using the LuxQED formalism, while QED evolution accounting for 
, 
, and 
corrections is implemented and benchmarked by means of the EKO code. We investigate the impact of QED effects on NNPDF4.0, and compare our results both to our previous NNPDF3.1QED PDF set and to other recent PDF sets that include the photon. We assess the impact of photon-initiated processes and electroweak corrections on a variety of representative LHC processes, and find that they can reach the 5% level in vector boson pair production at large invariant mass.
© The Author(s) 2024
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Funded by SCOAP3.
