Data Quality Monitoring for the CMS Resistive Plate Chamber Detector

Abstract

Resistive Plate Chambers (RPCs), with their excellent time resolution (∼ ns), were chosen as dedicated muon trigger detectors for the CMS experiment. RPCs fulfill the job of muon identification, estimate the momentum and unambiguously assign bunch crossing. The critical tasks of monitoring detector performance, debugging hardware, and certifying recorded data are carried out by the Data Quality Monitoring (DQM) system. The CMS DQM framework provides tools for creation, filling, storage, and visualization of histograms and scalar elements. It also offers standardized algorithms for performing statistical tests and automated data certification. Within this framework, the RPC DQM system was developed. The later is composed by a set of user defined algorithms and is intended to be used both online, during data taking, and offline, during the reconstruction stage at Tier-0 and re-reconstruction at the Tier-1s. Run by run, the system measures detector level and physics quantities which are subsequently stored in a dedicate database. We here describe the structure, functionalities, and performance of the DQM applications for the CMS RPC detector.