The Zeus calorimeter first level trigger

Conference · Sat Apr 01 04:00:00 EST 1989

DOI:https://doi.org/10.1016/0168-9002(94)01163-X· OSTI ID:123634

Smith, W J ^[1]

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1. Univ. of Wisconsin, Madison, WI (United States)

The design of the Zeus Detector Calorimeter Level Trigger is presented. The Zeus detector is being built for operation at HERA, a new storage ring that will provide collisions between 820 GeV protons and 30 GeV electrons in 1990. The calorimeter is made of depleted uranium plates and plastic scintillator read out by wavelength shifter bars into 12,864 photomultiplier tubes. These signals are combined into 974 trigger towers with separate electromagnetic and hadronic sums. The calorimeter first level trigger is pipelined with a decision provided 5 {mu}sec after each beam crossing, occurring every 96 nsec. The trigger determines the total energy, the total transverse energy, the missing energy, and the energy and number of isolated electrons and muons. It also provides information on the number and energy of clusters. The trigger rate needs to be held to 1 kHz against a rate of proton-beam gas interactions of approximately 500 kHz. The summed trigger tower pulseheights are digitized by flash ADC`s. The digital values are linearized, stored and used for sums and pattern tests.

• Research Organization: Lawrence Berkeley Lab., CA (United States). SSC Central Design Group
• OSTI ID: 123634
• Report Number(s): SSC-SR--1039; CONF-8901118--; ON: DE95011099
• Country of Publication: United States
• Language: English

Related Subjects

43 PARTICLE ACCELERATORS
44 INSTRUMENTATION
INCLUDING NUCLEAR AND PARTICLE DETECTORS
DESIGN
HERA STORAGE RING
NUCLEONS
SHOWER COUNTERS
STRUCTURE FUNCTIONS
SUPERCONDUCTING SUPER COLLIDER
TESTING
TRIGGER CIRCUITS