Search for single top production at HERA

摘要

A search for single top production in ep collisions using the completehigh-energy data from HERA is presented. This search is based on the analysis ofevents containing isolated leptons (electrons or muons) and missing transverse mo-ment um P_T~(miss)Inthe absence of a signal, an upper limit on the top productioncross-section σ_(epetX)<0.16 pb is established at the 95% confidence level, corre-sponding to an upper bound on the anomalous magnetic coupling K_(tuγ)<0.14. Thesearch is complemented by a search for events containing an isolated tau lepton andP_T~(miss) and the measurement ofWboson polarisation fractions.