2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/124337Events containing high-$P_T$ multi-leptons were sought at HERA by the H1 and ZEUS collaborations. Experimental data were compared to simulations of $γγ\to l^+ l^-$ processes, and H1 extracted the total and differential cross sections of the processes. The doubly-charged Higgs, which decays into lepton pairs, was analysed by H1 as a possible source of the multi-electron events, which have been observed at high invariant masses.5 pages, 5 figures, published in the proceedings of 11th International Workshop on Deep Inelastic Scattering (DIS 2003), St. Petersburg, Russia, 23-27 Apr 2003High Energy Physics - Experimenttext