Development of a high energy gamma-ray telescope for space flight using drift chambers

In order to continue the achievements in high-energy (10 MeV-100-GeV) gamma-ray astronomy made with the Energetic Gamma-Ray Experiment Telescope (EGRET) instrument on the Compton Gamma Ray Observatory (CGRO), a next-generation high-energy gamma-ray telescope with a large increase in sensitivity coupled with improved angular resolution will be required. This telescope is envisioned as a 2-m×2-m active area telescope using drift chambers for the imaging detector. The four major components of the instrument are the anticoincidence shield, the track imaging system, the coincidence/time-of-flight system, and the energy measurement system. The authors discuss the design goals and challenges for the four subsystems and the techniques being used to achieve them, as well as the design and performance of high-speed electronics that are being developed specifically for this application