Results from the commissioning of the ATLAS Pixel Detector with cosmic ray data

The ATLAS Pixel Detector is one of the largest silicon pixel hybrid detectors in the world. It has a total active area of 1.7 m2 of silicon read out every 25 ns by approximately 80 million electronic channels. It is the innermost tracking detector of the ATLAS experiment at the Large Hadron Collider (LHC) at CERN, designed to measure particle tracks and decay vertices with a very high precision and efficiency. Since August 2008, after more than 10 years of development and construction, the whole detector has been operated together. After tuning, calibration and timing-in the detector has demonstrated excellent noise occupancy of 10−10 and a tracking hit efficiency greater than 99.7%. The paper will describe the detector performance and discuss the studies performed with cosmic ray data, such as alignment and the Lorentz angle measurement.