A Gamma Ray Telescope Utilizing Large Area Wire Spark Chambers

A second generation gamma-ray telescope has been developed for further experiments in balloon-borne astronomy. This instrument is composed of 32 wire-grid spark chamber modules, each 50 × 50 cm2, utilizing two-coordinate ferrite core readout. The detector is flown on a 27 million cubic foot research balloon in a search for discrete gamma-ray sources and supernovae explosions.