Performance of the CMS Detector During the LHC Run 2

With the restart of the LHC operations in April 2015, the Run 2 has started. For the CMS Collaboration [1], the second half of the year was driven by an intense activity mainly ongoing on three fronts: analyses based on Run 1 data, studies for the upgrade of the detector in view of the future phases of the LHC and, of course, collect and analyse proton–proton and heavy ions data. This paper focuses on the latter highlighting examples where the intervention completed during the LHC Long Shutdown 1 (LS1) concretised in an improvement of the performance for the CMS detector and its hardware and software infrastructure.