Operational experience of the ATLAS pixel detector

The ATLAS Pixel Detector is situated in the heart of the ATLAS apparatus operating at the Large Hadron Collider. It was commissioned at the end of 2008 and since the start of the experimental run in March 2010 the detector is successfully participating in the reconstruction of tracks, vertices and tagging of short-lived particles. The fast readout and the hit identification are among the major challenges. The detector should be able to distinguish between hits in subsequent bunch crossings with a time interval 25 ns. After more than one year of LHC running at high luminosity, more than 2 fb−1 of collisions were recorded and significant operational experience was acquired. The Lorentz angle was determined as well as its temperature dependence. The particle ionization energy loss was extracted from the track clusters by means of a time-over-threshold method. Pixel cluster width in the direction of beam is studied in order to determine the collisions background.