First measurement of tW production cross-section at $\sqrt s$~= 13 TeV with CMS

Abstract: The inclusive cross-section for tW production in proton-proton collisions at $\sqrt{s} = 13$ TeV is measured for an integrated luminosity of 35.9 fb$^{-1}$ collected by the CMS experiment. The measurement is performed using events with one electron and one muon in the final state and at least one b-quark jet, and utilises kinematic differences between the signal and the dominating $t\bar{t}$ background using multivariant discriminants which is designed to disentangle the two processes. The measured cross-section of $\sigma = 63.1 \pm 1.8~({\rm stat}) \pm 6.4~({\rm syst}) \pm 2.1~({\rm lumi})$ pb is observed to be in agreement with the Standard Model.