$\mathrm{W}^{\pm}\gamma$ differential cross sections and effective field theory constraints at $\sqrt{s}=13\,\mathrm{TeV}$

Differential cross section measurements of $\mathrm{W}^{\pm}\gamma$ production in proton-proton collisions at $\sqrt{s} = 13\,\mathrm{TeV}$ are presented. The data set used in this study is collected with the CMS detector at the CERN LHC and corresponds to an integrated luminosity of $137\,\mathrm{fb}^{-1}$. Candidate events containing an electron or muon, a photon, and missing transverse momentum are selected. The measurements are compared to standard model predictions computed at next-to-leading order and next-to-next-to-leading order in perturbative quantum chromodynamics. Constraints on the presence of heavy new physics affecting the $\mathrm{WW}\gamma$ vertex are determined within an effective field theory framework, focusing on the $\mathcal{O}_{3W}$ operator. A simultaneous measurement of the photon transverse momentum and the azimuthal angle of the charged lepton in a special reference frame is performed. This two-dimensional approach yields sensitivity to the interference between the standard model and $\mathcal{O}_{3W}$ that is enhanced by up to a factor of ten compared to using the transverse momentum alone.