Alignment of the Inner Detector and of the Muon Spectrometer of the ATLAS experiment

The ATLAS experiment at the Large Hadron Collider at CERN is equipped with two tracking systems: the Inner Detector and the Muon Spectrometer. To achieve the desired tracking performance, these subdetectors have to be aligned with the precision of better than 10 micrometers for the Inner Detector and of better than 30 micrometers for the Muon Spectrometer. Track based alignment approaches in combination with optical sensor measurements are used to fullfill these requirements. The alignment corrections have been successfully applied to the LHC collision data. The results show that the precision of current alignment already allows for a good tracking performance.