The CMS high level trigger

  • The CMS Collaboration
Experimental Physics


At the Large Hadron Collider at CERN the proton bunches cross at a rate of 40 MHz. At the Compact Muon Solenoid experiment the original collision rate is reduced by a factor of \(\mathcal{O}\) (1000) using a Level-1 hardware trigger. A subsequent factor of \(\mathcal{O}\) (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.


Field Theory Elementary Particle Quantum Field Theory Large Hadron Collider Collision Rate 
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© Springer-Verlag 2006

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  • The CMS Collaboration

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