Commissioning of the CMS High-Level Trigger with Cosmic Rays

TL;DR

This paper describes the commissioning process of the CMS High-Level Trigger using cosmic rays, detailing trigger selection, data quality monitoring, and performance evaluation to ensure efficient data collection for the CMS experiment.

Contribution

It presents the deployment and performance assessment of the CMS HLT system during cosmic ray commissioning, including trigger algorithms and data quality tools.

Findings

HLT operated reliably during commissioning.

Trigger algorithms achieved efficient event selection.

Large datasets enabled comprehensive performance analysis.

Abstract

The CMS High-Level Trigger (HLT) is responsible for ensuring that data samples with potentially interesting events are recorded with high efficiency and good quality. This paper gives an overview of the HLT and focuses on its commissioning using cosmic rays. The selection of triggers that were deployed is presented and the online grouping of triggered events into streams and primary datasets is discussed. Tools for online and offline data quality monitoring for the HLT are described, and the operational performance of the muon HLT algorithms is reviewed. The average time taken for the HLT selection and its dependence on detector and operating conditions are presented. The HLT performed reliably and helped provide a large dataset. This dataset has proven to be invaluable for understanding the performance of the trigger and the CMS experiment as a whole.