Author/Authors :
J. Altegoer، نويسنده , , J. and Andrle، نويسنده , , J. and Boyd، نويسنده , , S. and Cardini، نويسنده , , A. and Farthouat، نويسنده , , P. and Ferrari، نويسنده , , R. and Geppert، نويسنده , , D. and Gِكling، نويسنده , , C. and Huta، نويسنده , , W. and Hyett، نويسنده , , N. and Koch، نويسنده , , N. and Lanza، نويسنده , , A. and Long، نويسنده , , J. and Moorhead، نويسنده , , G.F. and Pollmann، نويسنده , , D. and Poulsen، نويسنده , , C. and Rubbia، نويسنده , , A، نويسنده ,
Abstract :
The NOMAD trigger system is described in the present paper. It is made up of a large area plastic scintillator veto system, two trigger scintillator planes inside a 0.4 T magnetic field and their associated trigger electronics. Special features of the system consist of the use of proximity mesh photomultipliers which allow the trigger scintillators to operate in the magnetic field, and the use of custom-built VME modules which perform the trigger logic decisions, the signal synchronisation and gate generation, event counting and livetime calculations. This paper also includes a description of each of the NOMAD triggers, with their calculated and measured rates, efficiencies and livetimes.
