Nuclear Physics Seminar

The ATLAS silicon pixel detector is the innermost detector of the ATLAS experiment at the Large Hadron Collider at CERN. With approximately 80 million readout channels, the ATLAS pixel detector is a high-acceptance, high-resolution, low-noise tracking device.
Providing the desired refinement in charged track pattern recognition capability thus helping to meet the stringent particle track reconstruction requirements, the pixel detector largely defines the ability of ATLAS to effectively resolve the primary interaction and the secondary decay vertices, and to perform efficient quark flavor tagging that is essential for discovery of new physics.

Being the last sub-system installed in ATLAS by the end of June 2007, pixel detector was successfully connected, commissioned, and tested in situ while meeting the extremely tight operations schedule, and now has successfully collected its first collision data produced in the course of the turn-on of the LHC machine at the end of 2009. UT Dallas group has successfully deployed and commissioned the environmental controls for the opto-links, a crucial addition required for stable operation of the readout electronics of the pixel detector. Since fall 2008, the pixel detector has been included in the combined ATLAS detector operation, collecting physics data with cosmic rays. After a brief general introduction, the details from the pixel detector installation and commissioning, as well as the details on major hardware calibration procedures and the results obtained with the collected cosmic data, are presented. A few of the most recent results illustrating the combined inner tracking performance of the ATLAS detector with proton collisions, as well as the recent improvenents to calibration and allignment, will be discussed as well. The talk is concluded with the current ATLAS detector summary.