%0 Journal Article %@ 1434-6044 %A ZEUS Collaboration, The %D 2004 %F discovery:10069 %J The European Physical Journal C - Particles and Fields %N 3 %P 255-265 %T Search for QCD-instanton induced events in deep inelastic ep scattering at HERA %U https://discovery.ucl.ac.uk/id/eprint/10069/ %V 34 %X A search for QCD-instanton-induced events in deep inelastic ep scattering has been performed with the ZEUS detector at the HERA collider, using data corresponding to an integrated luminosity of 38 pb-1. A kinematic range defined by cuts on the photon virtuality, Q2 > 120 GeV2, and on the Bjorken scaling variable, x > 10-3, has been investigated. The QCD-instanton induced events were modelled by the Monte Carlo generator QCDINS. A background-independent, conservative 95% confidence level upper limit for the instanton cross section of 26 pb is obtained, to be compared with the theoretically expected value of 8.9 pb. %Z The ZEUS Collaboration includes the following UCL authors: S. Boutle, J.M. Butterworth, C. Gwenlan, R. Hall-Wilton, T.W. Jones, J.H. Loizides, D. Nicholass, M.R. Sutton, C. Targett-Adams and M. Wing.