A search for physics beyond the standard model (SM) in final states with an electron or muon and missing transverse momentum is presented. The analysis uses data from proton-proton collisions at a center-of-mass energy of 13 TeV, collected with the CMS detector at the LHC in 2016–2018, corresponding to an integrated luminosity of 137 fb-1. No significant deviation from the SM prediction is observed. Model independent limits are set on the production cross section and coupling strength of W' bosons decaying into lepton-plus-neutrino final states. This analysis also sets limits on the parameters of other models beyond-the-SM. A 5.7 TeV exclusion limit at 95% confidence level on the mass of a sequential SM W' boson with SM-like couplings is found, when combining electron and muon decay channels. Results on oblique electroweak parameters, in particular on the W parameter, are also presented for the first time using LHC data. These results are combined with those from the direct resonance search to set constraints on composite Higgs scenarios.

$p_{T}^{miss}$ distribution in the electron channel using 2016-2018 data sets. The complete set of selection criteria were applied. Two examples of SSM WPRIME boson signal samples with masses of 3.8 and 5.6 TeV are shown. The lower panel shows the ratio of data to SM prediction, and the shaded band represents the systematic uncertainties.