Aaboud, M.Albert, JustinChiu, Y. H.Elliott, Alison A.Fincke-Keeler, J.Hamano, KenjiHill, Ewan ChinKeeler, RichardKowalewski, RobertKuwertz, E. S.Kwan, TonyLeBlanc, Matthew EdgarLefebvre, MichelMcPherson, Robert A.Seuster, RolfSobie, Randall J.Trovatelli, M.Venturi, M.ATLAS Collaboration2020-02-182020-02-1820172017Aaboud, M.; Aad, G.; Abbott, B.; Abdinov, O.; Abeloos, B.; Abidi, S. H.; … & Zwalinski, L. (2017). Study of WW gamma and WZ gamma production in pp collisions at root s=8 TeV and search for anomalous quartic gauge couplings with the ATLAS experiment. The European Physical Journal C, 77(9), article 646. DOI: 10.1140/epjc/s10052-017-5180-3https://doi.org/10.1140/epjc/s10052-017-5180-3http://hdl.handle.net/1828/11564This paper presents a study of WWγ and WZγ triboson production using events from proton–proton collisions at a centre-of-mass energy of s√=8TeV recorded with the ATLAS detector at the LHC and corresponding to an integrated luminosity of 20.2 fb−1. The WWγ production cross-section is determined using a final state containing an electron, a muon, a photon, and neutrinos (eνμνγ). Upper limits on the production cross-section of the eνμνγ final state and the WWγ and WZγ final states containing an electron or a muon, two jets, a photon, and a neutrino (eνjjγ or μνjjγ) are also derived. The results are compared to the cross-sections predicted by the Standard Model at next-to-leading order in the strong-coupling constant. In addition, upper limits on the production cross-sections are derived in a fiducial region optimised for a search for new physics beyond the Standard Model. The results are interpreted in the context of anomalous quartic gauge couplings using an effective field theory. Confidence intervals at 95% confidence level are derived for the 14 coupling coefficients to which WWγ and WZγ production are sensitive.enArticleDepartment of Physics and Astronomy