The L3 energy trigger for the LEP 8 bunch operation

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Abstract

The first level energy trigger of the L3 experiment at LEP has been presented at this Conference in 1989. It is based on energy measurements in the electromagnetic and hadronic calorimeters and in the luminosity monitors and has been designed to take a decision in less than 22.2 μs, the time between two bunch crossings in the LEP interaction region. In 1992 it is planned to operate LEP in 8×8 bunch mode with a bunch crossing interval of 11.1 μs. The energy trigger has therefore been modified to efficiently cope with the new situation. For the triggers based on the luminosity monitors information, due to the small amount of data to be processed, it has been possible to reduce the decision time to below 9 μs. For the triggers based on calorimetric information, a new level of trigger, level-0 or pre-trigger has been introduced which in about 9 μs takes a fast, preliminary decision. Only if this decision is positive the calorimetric trigger processing is completed with the loss of one beam crossing. A new fast module, the dual input memory (DIM), has been designed and built to make possible this new mode of operation.

References (4)

  • B. Adeva

    Nucl. Instr. and Meth.

    (1990)
  • R. Bizzarri

    Nucl. Instr. and Meth.

    (1989)
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