Performance of the EGRET astronomical gamma ray telescope

Abstract
On April 5, 1991, the Space Shuttle Atlantis carried theCompton Gamma Ray Observatory (CGRO) into orbit,deploying the satellite on April 7. The EGRET instrumentwas activated on April 15, and the first month of operationswas devoted to verification of the instrument performance.Measurements made during that month and inthe subsequent sky survey phase have verified that the instrumenttime resolution, angular resolution, and gammaray detection efficiency are all within nominal limits.I....