The GLAST large area telescope: Design, construction, test and calibration

The Gamma-ray Large Area Space Telescope (GLAST) is an international, multi-agency satellite mission with a vast and ambitious physics program in gamma-ray astronomy, particle astrophysics and cosmology. The Large Area Telescope (LAT) is the main instrument onboard GLAST and will detect high energy gamma rays with unprecedented resolution and sensitivity. After successful integration of the three detector subsystems—a silicon-strip tracker-converter, a CsI imaging calorimeter and an outer plastic scintillator serving as anti-coincidence detector—into the telescope, the LAT was installed on the satellite in preparation for the January 2008 launch. Highlights of the LAT instrument performance and of the main technological challenges encountered during the telescope design, commissioning and calibration phases are discussed here, as well as their impact on the mission discovery potential.