The search for top in UA1

The search for top-quark and possibly other non known heavy quarks decaying semileptonically into muons is being continued by UA1. The preliminary results presented here are based on the data collected in the 1988 and 1989 CERN antipp Collider runs corresponding to 4.6 pb-1. Three different samples have been analyzed: events with one muon accompanied by jets, events with two muons and events with one muon and one electron. No top signal has been observed. Combining the three channels and the UA1 published data a new preliminary lower limit on the top-quark mass is obtained at 61 GeV (95% c.l.)