Experimental search for chargino and neutralino production in supersymmetry models with a light gravitino

Abstract

We search for inclusive high E_T diphoton events with large missing transverse energy in pp̅ collisions at √s=1.8 TeV. Such events are expected from pair production of charginos and neutralinos within the framework of the minimal supersymmetric standard model with a light gravitino. No excess of events is observed. In that model, and assuming gaugino mass unification at the GUT scale, we obtain a 95% C.L. exclusion region in the supersymmetry parameter space and lower mass bounds of 150 GeV/c² for the lightest chargino and 77 GeV/c² for the lightest neutralino.