ANGULAR DISTRIBUTION OF SKYSHINE RADIATION AT THE SURFACE OF A PLANE OF FALLOUT CONTAMINATION

Abstract : An experimental program was conducted to determine the angular distribution of the air-scattered component of gamma radiation (skyshine) at the surface of a plane of fallout contamination. Measurements were made by placing a radiation detector in a vertical collimator recessed flush with the ground surface and placing cobalt60 sources on the ground along a line extending from the center of the collimator to a radius of about 40 ft to simulate fallout contamination. Detector depth in the collimator was varied to measure skyshine within the cone formed by the collimator opening and the detector at given solid angle fractions for source positions extending from the collimator lip to the 40-ft radius. The experimentally-determined results of this program and of other investigators were compared with theoretical calculations. (Author)