Search for 3- and 4-body decays of the scalar top quark in pp̄ collisions at s= 1.8 TeV

Abstract We have searched for the signature of 3- and 4-body decays of pair-produced scalar top quarks (stop) in the inclusive final state containing an electron, a muon, and significant missing transverse energy using a sample of p p events corresponding to 108.3 pb −1 of data collected with the DO detector at Fermilab. The search is done in the framework of the minimal supersymmetric standard model assuming that the neutralino ( χ 0 1 ) is the lightest supersymmetric particle and is stable. No evidence for a signal is found and we derive cross-section upper limits as a function of stop ( t ) and neutralino masses in different decay scenarios leading to the blν χ 0 1 final state.