Search for new resonances decaying to a charged lepton and a neutrino in pp collisions at $\sqrt{s} = 13$ TeV with the ATLAS detector

In this note a search for $W^\prime$ bosons decaying to a charged lepton (electron or muon) and a neutrino is presented. For this search $13.3~fb^{−1}$ of $pp$ collision data are used which were collected at $\sqrt{s} = 13$ TeV by the ATLAS experiment at the LHC in 2015 and 2016. The transverse mass distribution is examined and no significant excess above Standard Model predictions is observed. Upper limits on the $W^\prime$ boson cross-section times branching ratio to leptons are set as a function of the $W^\prime$ mass. Assuming a $W^\prime$ boson with Standard Model couplings to fermions, $W^\prime$ masses below $4.74$ TeV are excluded at the $95$% confidence level. This improves upon the current ATLAS limit based on the $3.2~fb^{−1}$ of collision data taken in 2015 by around 700 GeV.