SINGLE LEPTON PRODUCTION AT LARGE TRANSVERSE-MOMENTUM

We study the production of single isolated leptons at large transverse momentum, p(T)l > 1/2 M(W). The dominant source of such leptons is pr oduction of an on-shell W boson recoiling against a hard jet. Vetoing this jet forces the W boson to be produced off resonance and significa ntly reduces the standard model cross section, thereby enhancing the d iscovery prospects for non standard model physics. A significant numbe r of events have the topologically interesting signature of a large p( T) lepton balancing a jet with little measured missing transverse ener gy.