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arXiv · hep-ex/0512077

The CMS High Level Trigger

The CMS Trigger·Data Acquisition Group
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Abstract

At the Large Hadron Collider at CERN the proton bunches cross at a rate of 40MHz. At the Compact Muon Solenoid experiment the original collision rate is reduced by a factor of O (1000) using a Level-1 hardware trigger. A subsequent factor of O(1000) data reduction is obtained by a software-implemented High Level Trigger (HLT) selection that is executed on a multi-processor farm. In this review we present in detail prototype CMS HLT physics selection algorithms, expected trigger rates and trigger performance in terms of both physics efficiency and timing.

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The CMS Trigger, Data Acquisition Group. 2005-12-31. The CMS High Level Trigger. https://doi.org/10.1140/epjc%2Fs2006-02495-8

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