Events with an Isolated Lepton and Missing Transverse Momentum and Measurement of W Production at HERA

Understand

A search for events containing an isolated electron or muon and missing transverse momentum produced in ep collisions is performed with the H1 and ZEUS detectors at HERA.

• The data were taken in the period 1994-2007 and correspond to an integrated luminosity of 0.98 fb^-1.
• The observed event yields are in good overall agreement with the Standard Model prediction, which is dominated by single W production.
• In the e+p data, at large hadronic transverse momentum PtX >25 GeV, a total of 23 events are observed compared to a prediction of 14.0 \pm 1.9.