Tracking and Vertexing with the ATLAS Detector at the LHC

The ATLAS experiment is one of the two general purpose detectors at the Large Hadron Collider. ATLAS is equipped with a charged particle tracking system (Inner Detector) built on three subdetectors, which provide high precision measurements made from a fine detector granularity. The pixel and microstrip subdetectors, which use the silicon technology, are complemented with the transition radiation tracker. We will report on the performance of the track and vertex reconstruction of the ATLAS Inner Detector using the data recorded since December 2009 at center-of-mass energies of 0.9 and 7 TeV. In particular results on tracking efficiency and track impact parameter resolution, particle identification and reconstruction as well as primary vertex performance will be discussed. The detection of secondary vertices, which are crucial for b-tagging algorithms based upon the long lifetime of b-hadron decays will also be presented.