Digitized Spark Chamber for Space Science Experiments

A digitized spark chamber has been developed for gamma-ray and charged particle experiments on balloons and satellites. The spark chamber is assembled from modular units, which are stacked to the desired number of levels. Each module consists of parallel spark planes formed from two orthogonal wire grids. Ferrite memory cores, strung on the wires of both grids, record the X-Y coordinate of the spark. Factors affecting the operating characteristics of these modules are discussed. A gamma-ray detector of 32 module levels has been assembled and balloon-flown in a search for cosmic gamma-ray point sources. The construction of this detector is described and its performance briefly discussed.