The CMS collaboration2021-02-102021-02-102020The CMS collaboration. "Observation of electroweak production of Wγ with two jets in proton-proton collisions at s= 13 TeV." <i>Physics Letters B,</i> 811, (2020) Elsevier: https://doi.org/10.1016/j.physletb.2020.135988.https://hdl.handle.net/1911/109841A first observation is presented for the electroweak production of a W boson, a photon, and two jets in proton-proton collisions. The W boson decays are selected by requiring one identified electron or muon and an imbalance in transverse momentum. The two jets are required to have a high dijet mass and a large separation in pseudorapidity. The measurement is based on data collected with the CMS detector at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 35.9 . The observed (expected) significance for this process is 4.9 (4.6) standard deviations. After combining with previously reported CMS results at 8 TeV, the observed (expected) significance is 5.3 (4.8) standard deviations. The cross section for the electroweak production in a restricted fiducial region is measured as and the total cross section for Wγ production in association with 2 jets in the same fiducial region is . All results are in good agreement with recent theoretical predictions. Constraints are placed on anomalous quartic gauge couplings in terms of dimension-8 effective field theory operators.engThis is an open access article under the CC BY licenseJournal articleObservation-of-electroweak-productionhttps://doi.org/10.1016/j.physletb.2020.135988