Monitoring and improving the ALICE data taking efficiency

Abstract

ALICE (A Large Ion Collider Experiment) is the heavy-ion experiment designed to study the physics of strongly interacting matter and the quark-gluon plasma at the CERN Large Hadron Collider (LHC). Since its successful start-up in 2010, the LHC has been performing outstandingly, providing to the experiments long periods of stable collisions and an integrated luminosity that greatly exceeds the planned targets. To fully explore these privileged conditions, it is paramount that the experiment's data taking efficiency during stable collisions is as high as possible. In ALICE, some of the greatest lessons learned in 2011 were how important it is to clearly identify the reasons of inefficiency, closely monitor the efficiency and make the information available to the whole collaboration. This paper will describe how the ALICE Electronic Logbook (eLogbook) is used to recognize the main causes of inefficiency, helping decision making by providing quantitative information and allowing the Run Coordination team to identify, prioritize, address and follow them. It will also explain how the eLogbook is used to monitor the data taking efficiency, providing reports that allow the collaboration to portray its evolution and evaluate the measures taken to increase it. Finally, it will present the ALICE efficiency since the start-up of the LHC and the future plans to further support the Run Coordination activities.