2009/08/07 by L. Agostino, Lorenzo Agostino, Gerry Bauer +92 · 1 citation
Engineering · Physics and Astronomy · #Particle Accelerators and Free-Electron Lasers #Particle Detector Development and Performance #Particle accelerators and beam dynamics #physics.ins-det
paper · pdf · doi:10.1088/1748-0221/4/10/p10005
published as JINST 4:P10005,2009
arxiv created 2009/08/07 · openalex publication_date 2009/10/19 · arxiv updated 2009/12/01 · openalex created_date 2020/11/23 · openalex updated_date 2026/08/04
The CMS experiment will collect data from the proton-proton collisions delivered by the Large Hadron Collider (LHC) at a centre-of-mass energy up to 14 TeV. The CMS trigger system is designed to cope with unprecedented luminosities and LHC bunch-crossing rates up to 40 MHz. The unique CMS trigger architecture only employs two trigger levels. The Level-1 trigger is implemented using custom electronics, while the High Level Trigger (HLT) is based on software algorithms running on a large cluster of commercial processors, the Event Filter Farm. We present the major functionalities of the CMS High Level Trigger system as of the starting of LHC beams operations in September 2008. The validation of the HLT system in the online environment with Monte Carlo simulated data and its commissioning during cosmic rays data taking campaigns are discussed in detail. We conclude with the description of the HLT operations with the first circulating LHC beams before the incident occurred the 19th September 2008.