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arXiv · hep-ex/0202045

The multilevel trigger system of the DIRAC experiment

L. Afanasyev·M. Gallas·D. Goldin·A. Gorin·V. Karpukhin·P. Kokkas·A. Kulikov·K. Kuroda·I. Manuilov·K. Okada·C. Schuetz·A. Sidorov·M. Steinacher·F. Takeutchi·L. Tauscher·S. Vlachos·V. Yazkov
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Abstract

The multilevel trigger system of the DIRAC experiment at CERN is presented. It includes a fast first level trigger as well as various trigger processors to select events with a pair of pions having a low relative momentum typical of the physical process under study. One of these processors employs the drift chamber data, another one is based on a neural network algorithm and the others use various hit-map detector correlations. Two versions of the trigger system used at different stages of the experiment are described. The complete system reduces the event rate by a factor of 1000, with efficiency $\geq$95% of detecting the events in the relative momentum range of interest.

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L. Afanasyev, M. Gallas, D. Goldin, A. Gorin, V. Karpukhin, P. Kokkas, A. Kulikov, K. Kuroda, I. Manuilov, K. Okada, C. Schuetz, A. Sidorov, M. Steinacher, F. Takeutchi, L. Tauscher, S. Vlachos, V. Yazkov. 2002-02-28. The multilevel trigger system of the DIRAC experiment. https://doi.org/10.1016/s0168-9002(02)01277-9

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