14-18 October 2013
Amsterdam, Beurs van Berlage
Europe/Amsterdam timezone

The CMS High Level Trigger

17 Oct 2013, 11:00
Verwey Kamer (Amsterdam, Beurs van Berlage)

Verwey Kamer

Amsterdam, Beurs van Berlage

Oral presentation to parallel session Data acquisition, trigger and controls Data Acquisition, Trigger and Controls


Daniele Trocino (Northeastern University (US))


The CMS experiment has been designed with a 2-level trigger system: the Level 1 Trigger, implemented on custom-designed electronics, and the High Level Trigger (HLT), a streamlined version of the CMS offline reconstruction software running on a computer farm. A software trigger system requires a tradeoff between the complexity of the algorithms running on the available computing power, the sustainable output rate, and the selection efficiency. Here we will present the performance of the main triggers used during the 2012 data taking, ranging from simpler single-object selections to more complex algorithms combining different objects, and applying analysis-level reconstruction and selection. We will discuss the optimisation of the triggers and the specific techniques to cope with the increasing LHC pile-up, reducing its impact on the physics performance.

Primary author

Daniele Trocino (Northeastern University (US))

Presentation Materials