The ZEUS second level calorimeter trigger: Physics simulation, design and implementation
Abstract
The ZEUS detector for HERA (German acronym for hadron electron storage ring) is addressed. HERA parameters and physics potential are discussed. One of the main detector components of the ZEUS experiment is the high resolution depleted uranium scintillator sandwich calorimeter, which plays an important role in the (offline) reconstruction of the recorded events and in the (online) selection of the interesting events. The ZEUS detector is described with emphasis on the high resolution calorimeter and on data acquisition and triggering. The performance of the trigger algorithm implemented in a specially developed tansputer based VME module was tested using Monte Carlo events and the Monte Carlo event generators used are discussed. First level trigger studies on Monte Carlo data are discussed. The input rates for both the first and second level trigger turn out to be completely dominated by interactions of the proton beam with the rest gas in the beam pipe in a range between -60 m and + 2 m from the interaction point. Important results of the second level calorimeter trigger processor algorithm are presented. The efficiency and reliability for the recognition of electrons and jets by the second level calorimeter trigger processor were shown to be satisfactory. It is shown that with the use of the calorimeter cluster information a significant beam gas event suppression, by a factor larger than 10, can be obtained, while the interesting events are not significantly affected.
- Publication:
-
Ph.D. Thesis
- Pub Date:
- September 1990
- Bibcode:
- 1990PhDT........14D
- Keywords:
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- Algorithms;
- Calorimeters;
- Data Acquisition;
- High Resolution;
- Monte Carlo Method;
- Particle Collisions;
- Electron Accelerators;
- Events;
- Hadrons;
- Radiation Counters;
- Transputers;
- Atomic and Molecular Physics