Search for a new heavy gauge-boson resonance decaying into a lepton and missing transverse momentum in 36 fb ${}^{-1}$ of pp collisions at $\sqrt{s}=13$ TeV with the ATLAS experiment

The results of a search for new heavy ${W}^{\prime }$ bosons decaying to an electron or muon and a neutrino using proton–proton collision data at a centre-of-mass energy of $\sqrt{s}\phantom{\rule{3.33333pt}{0ex}}=\phantom{\rule{3.33333pt}{0ex}}13$ TeV are presented. The dataset was collected in 2015 and 2016 by the ATLAS experiment at the Large Hadron Collider and corresponds to an integrated luminosity of 36.1 $\phantom{\rule{0.333333em}{0ex}}\text{fb}{\phantom{\rule{0.333333em}{0ex}}}^{-1}$ . As no excess of events above the Standard Model prediction is observed, the results are used to set upper limits on the ${W}^{\prime }$ boson cross-section times branching ratio to an electron or muon and a neutrino as a function of the ${W}^{\prime }$ mass. Assuming a ${W}^{\prime }$ boson with the same couplings as the Standard Model W boson, ${W}^{\prime }$ masses below 5.1 TeV are excluded at the 95% confidence level.