Measurement of the electroweak production of W$\gamma$ in association with two jets in proton-proton collisions at $\sqrt{s}$ = 13 TeV

A measurement is presented for the electroweak production of a W boson, a photon (γ), and two jets (j) in
proton-proton collisions. The leptonic decay of the W boson is selected by requiring one identified electron
or muon and large missing transverse momentum. The two jets are required to have large invariant dijet
mass and large separation in pseudorapidity. The measurement is performed with the data collected by the
CMS detector at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of
138 fb−1. The cross section for the electroweak Wγjj production is 23.5þ4.9 −4.7 fb, whereas the total cross
section for Wγjj production is 113 13 fb. Differential cross sections are also measured with the
distributions unfolded to the particle level. All results are in agreement with the standard model
expectations. Constraints are placed on anomalous quartic gauge couplings (aQGCs) in terms of
dimension-8 effective field theory operators. These are the most stringent limits to date on the aQGCs
parameters fM;2–5=Λ4 and fT;6–7=Λ4.