Advanced Alignment of the ATLAS Inner Detector

The primary goal of the ATLAS Inner Detector (ID) is to accurately measure the trajectories of charged particles in the high particle density environment of the Large Hadron Collider (LHC) collisions. This is achieved using a combination of different technologies, including silicon pixels, silicon microstrips, and gaseous drift-tubes, all immersed in a 2 Tesla magnetic field. With over one million alignable degrees of freedom, it is crucial that an accurate model of the detector positions be produced using an automated and robust algorithm in order to achieve good tracking performance. This has been accomplished using a variety of alignment techniques resulting in near optimal hit and momentum resolutions.