ATLAS Inner Detector developments

The ATLAS Inner Detector consists of three layers of silicon pixel detectors, four double layers of silicon microstrip detectors and a straw tube based Transition Radiation Tracker. The good performance of the track and vertex reconstruction algorithms is a direct consequence of the small radius (4.3, 10.1 and 13.2 cm), fine pitch (50×300 μm) and low occupancy (<3×10−4 at design luminosity) of the pixel detectors, and of the good tracking capabilities of the silicon microstrip detector system and the transition radiation tracker. The full detector simulation is used to evaluate the performance of the detector and of the reconstruction algorithms. Results are presented on track and vertex reconstruction efficiencies and resolutions, and on the separation between b-jets and jets produced by light quarks.