Search for direct top squark pair production in events with one lepton, jets and missing transverse energy at 13 TeV

A search for direct top squark pair production is presented. The search is based on proton-proton collision data at a center-of-mass energy of $13~\mathrm{TeV}$ recorded by the CMS experiment at the LHC during 2016, 2017 and 2018, corresponding to an integrated luminosity of $137~\mathrm{fb}^{-1}$. The search is carried out using events with a single isolated electron or muon, multiple jets, and large transverse momentum imbalance. The observed data are consistent with expectations from standard model processes. Exclusions are set in the context of simplified top squark pair production models. Depending on the model, exclusion limits at $95\%$ confidence level for top squark masses up to $1.2~\mathrm{TeV}$ are set for a massless lightest supersymmetric particle. For models with top squark masses of $1~\mathrm{TeV}$, neutralino masses up to $600~\mathrm{GeV}$ are excluded.