Quality Assurance and Data Quality Monitoring for the ALICE Silicon Drift Detectors

Abstract

In this paper, the Quality Assurance (QA) and Data Quality Monitoring (DQM) of the ALICE Silicon Drift Detectors will be discussed. The Quality Assurance functionality has been implemented as part of AliRoot, the ALICE software framework, so as to use the same code in offline and online mode. The QA system manages the three sub-detectors of the Inner Tracking System (ITS) in a modular way, in order to run the Quality Assurance of all or just one of them, creating the QA distributions for the selected detector(s). The ITS-QA framework can also be used for the online monitoring of the sub-detectors thanks to its interface to the AMORE (Automatic MonitoRing Environment) Data Quality Monitoring (DQM) framework, in turn interfaced to the Data Acquisition System. The online mode is steered by a specific subdetector agent that makes use of functionality provided by AMORE to connect and receive events from the Data Acquisition System, invokes AliRoot code for their reconstruction and analysis and for filling the QA distributions and then handles these distributions to AMORE that publishes them to its Database. A dedicated GUI allows the operators to retrieve and display the subdetector QA distributions from the AMORE Database. The SDD QA and DQM are fully operational since the beginning of the ALICE data taking and are important tools to assess the data quality both in real time and in the offline analysis.