Observation of $Wγγ$ triboson production in proton-proton collisions at s=13 TeV with the ATLAS detector

• Published in: Physics letters. B Vol. 848
• Main Authors: Alberghi, G. L., Atkinson, M., Bailey, V. R., Baldin, E. M., Barberis, D., Barr, J. D., Bechtle, P., Bhatta, S., Bobbink, G. J., Boehler, M., Boudreau, J., Callea, G., Charlton, D. G., Chen, S., Chomont, A. R., Coelli, S., Curcio, F., Das, S. J., Davis-Purcell, B., Delmastro, M., Diehl, E. B., Dimitriadi, C., Dittmeier, S. J., Djama, F., Feng, C., Filipčič, A., Fleck, I., Fomin, N., Guida, A., Hanagaki, K., Hillier, S. J., Ibragimov, I., Ivina, A., Izen, J. M., Jamieson, J., Jessiman, C. E., Jiang, Y., Karkanias, I., Klein, C., Klioutchnikova, T., Krieger, P., Kuze, M., Kvita, J., Lacker, H., Lad, N. N., Lai, S., Lampl, W., Leroy, C., Li, A., Li, B., Liu, J. B., Lu, M., Lytken, E., Ma, L. L., Martinez Outschoorn, V. I., Maurer, J., Meshkov, O., Mizukami, A., Moschovakos, P., Mosidze, M., Olivares Pino, S. A., Parajuli, S., Pettee, M., Pettersson, N. E., Piazza, F., Piper, K. M., Ponomarenko, D., Portillo Quintero, D. M., Rendel, M. B., Rennie, A. G., Rougier, C., Rozen, Y., Russell, H. L., Russo, G., Safai Tehrani, F., Sauerburger, F., Shrestha, S., Simoniello, R., Sinha, S., Sioli, M., Solomon, S., Spousta, M., Ströhmer, R., Talyshev, A. A., Tanaka, A., Taylor, G. N., Todorova-Nova, S., Tosciri, C., Trigger, I. M., Tsuno, S., Vermeulen, J. C., Viehhauser, G. H.A., Vittori, C., White, A. S., Yang, H. T., Yorita, K., Yuan, M., Zambito, S., Zhang, D. F., Zheng, X.
• Format: Journal Article
• Language: English
• Published: United States Elsevier 14.12.2023
• Subjects: INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
• ISSN: 0370-2693

This letter reports the observation of W(ℓν)γγ production in proton-proton collisions. This measurement uses the full Run 2 sample of events recorded at a center-of-mass energy of $\sqrt{s}$ = 13 TeV by the ATLAS detector at the LHC, corresponding to an integrated luminosity of 140 fb-1. Events with a leptonically-decaying W boson and at least two photons are considered. The background-only hypothesis is rejected with an observed and expected significance of 5.6 standard deviations. The inclusive fiducial production cross section of W(eν)γγ and W(μν)γγ events is measured to be σfid = 13.8 ± 1.1(stat) $^{+2.1}_{-2.0}$(syst) ± 0.1(lumi) fb, in agreement with the Standard Model prediction.