Absolute fission yield measurements by track-etch-cum-γ spectroscopy

As part of a long range program of absolute fission yield measurements in the neutron induced fission of actinide isotopes with emphasis on minimising the various sources of error in the measurements, a fission track-cum-γ-ray spectrometric method has been developed where the total number of fissions occurring in the target is determined directly with an accuracy of 2 to 3%. The fission product atoms formed are determined by direct γ-ray spectrometry using a Ge(Li) detector coupled to a multichannel analyser. The feasibility of this method has been established by measuring the yield of several fission products in the thermal neutron induced fission of 235U and 239Pu, where the data agreed within 1 to 5% of the best available literature values. The various aspects of the technique are discussed in comparison with other absolute fission yield measurement techniques. The merit, scope and relevance of the method are also discussed. (author)