(en) A search for events containing two or more high-transverse-momentum isolated leptons has been performed in ep collisions with the ZEUS detector at HERA using the full collected data sample, corresponding to an integrated luminosity of 480 pb^{-1}. The number of observed events has been compared with the prediction from the Standard Model, searching for possible deviations, especially for multi-lepton events with invariant mass larger than 100 GeV. Good agreement with the Standard Model has been observed. Total and differential cross sections for di-lepton production have been measured in a restricted phase space dominated by photon-photon collisions. Comment: 18 pages, 5 figures. v2: revised version for journal publication
Chekanov, S., de Favereau de Jeneret, J., & et al. (2009). Multi-lepton production at high transverse momentum at HERA. Physics Letters. Section B: Nuclear, Elementary Particle and High-Energy Physics, B680, 13-23. https://doi.org/10.1016/j.physletb.2009.08.026 (Original work published 2009)