THE TIGRE INSTRUMENT FOR 0.3-100 MEV GAMMA-RAY ASTRONOMY

The Tracking and Imaging Gamma-Ray Experiment(4) (TIGRE) uses multilay ers of silicon strip detectors both as a gamma-ray converter and to tr ack Compton recoil electrons and positron-electron pairs. The directio n and energy of the Compton scattered gamma ray and pair particles are measured with arrays of small CsI(Tl)-photodiode detectors. With a la rge pi-steradian field-of-view, the prototype instrument described her e is sensitive to gamma rays from 0.3 to 100 MeV with a typical energy resolution of 3% (FWHM) and a 1-sigma angular resolution of 120 are m in. at 2 MeV. It has a high absolute detection efficiency of 8% over t he full energy range. The telescope will be described and Monte Carlo calculations will be presented. Measurements with a small desktop inst rument are presented elsewhere in this volume.