A trigger system using cathode read-out chambers and fast computing of kinematical quantities

Abstract

We describe a system of cathode read-out multiwire proportional chambers which performs the trigger of a spectrometer installed at the CERN S.P.S. to study high mass dimuon pairs. These chambers, associated with fast ECL circuitry, allow to select particles with high tranverse momentum in less than 110 ns. A further development of the electronics will permit to trigger on high dimuon masses with a response time of the order of 170 ns.