CERN Accelerating science

LHC data

ATLAS trigger system meets the challenges of Run 2

The trigger system is an essential component of any collider experiment as it is responsible for deciding whether or not to keep an event from a given bunch-crossing interaction for later study. During Run 2 (2015 to 2018) of the Large Hadron…

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Trigger strategies for the LHCb experiment

The LHCb experiment has finished a very successful data taking period in Run 2, collecting an additional 6 inverse femtobarns of proton-proton collisions. A significant modification to the Reconstruction and Trigger system of LHCb was implemented…

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CMS Trigger: Lessons from LHC Run 2

The CMS experiment has a two-level trigger system [1], to reduce the number of events stored from the LHC bunch crossing rate of 40 MHz to around 1 kHz. The first level (the Level-1) uses custom electronics to reduce the rate of events to 100 kHz,…

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