抄録
A method is devised to obtain gamm-rays of Compton single scattering effectively monochromatized in gradated energies.
A scatterer in a form of a strip is bent circularly in curvature of a circle on which a gammarays source, a detector and the scatterer are placed. The gamma-rays that are scattered at all the points of the scatterer and reach the detector are of the same angle of scattering because of the circular configuration, thus attaining effective focusing of monochromatic scattered gamma-rays. Gamma-rays of differently gradated energies are obtained by shifting the detector to different positions on the circumference.
To obtain intense and well qualified rays, considerations are given to scatterer material, stray radiation and geometry of the configuration.
From some results with a cesium-137 source and an iron scatterer of 1.6mm in thickness, intensity of the obtained rays is proportional to the mass of the scatterer up to 60 grams or more. Because of Compton multiple scattering in the scatterer, the monochromatic nature becomes worse when a large scatterer is used, but when compared with a block scatterer of the same mass, even at the mass of several 100 grams, the quality of the obtained rays is considerably better with the circular scatterer than with the block scatterer.
The energy shift of the obtained rays by a slight deviation of the scatterer from the prescribed geometry is negligible except in the neighbourhood of the source and the detector.
