ATLAS collaboration (2876 authors)Aguilar-Saavedra, Juan AntonioAmor Dos Santos, Susana PatriciaAnjos, NunoAraque, Juan PedroCastro, Nuno FilipeConde Muiño, PatriciaDa Cunha Sargedas De Sousa, Mario JoseFiolhais, MiguelGalhardo, BrunoGomes, AgostinhoGonçalo, RicardoJorge, PedroMachado Miguens, JoanaMaio, AméliaManeira, JoséOleiro Seabra, Luis FilipeOnofre, AntónioPedro, RuteSantos, HelenaSaraiva, JoãoSilva, JoséTavares Delgado, AdemarVeloso, FilipeWolters, Helmut2019-02-042019-02-042017-09-25http://dx.doi.org/10.1140/epjc/s10052-017-5180-3http://hdl.handle.net/10400.26/27394This paper presents a study of $WW\gamma $ and $WZ\gamma $ triboson production using events from proton–proton collisions at a centre-of-mass energy of $\sqrt{s} = \text{8}\,\text{TeV}$ recorded with the ATLAS detector at the LHC and corresponding to an integrated luminosity of 20.2 fb$^{-1}$ . The $WW\gamma $ production cross-section is determined using a final state containing an electron, a muon, a photon, and neutrinos ( $e\nu \mu \nu \gamma $ ). Upper limits on the production cross-section of the $e\nu \mu \nu \gamma $ final state and the $WW\gamma $ and $WZ\gamma $ final states containing an electron or a muon, two jets, a photon, and a neutrino ( $e\nu jj\gamma $ or $\mu \nu jj\gamma $ ) 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 $WW\gamma $ and $WZ\gamma $ production are sensitive.engjournal article2019-02-04