A method for determining quantitatively the content of fissile material in small size particles

摘要

This invention refers to a method for the quantitative determination of the fissile material content in small size particles present in samples such as environmental samples. According to the invention, the "fission track process", known per se, is applied to said samples, according to which the samples are sandwiched in organic sheets and then submitted to a defined thermal neutron fluence whereupon fission products of the fissile material in the sample create in the sheets fission tracks which are rendered visible by etching the sheets. Then the size of selected particles having created such tracks is determined by means of an appropriate microscope and thereafter these visible tracks of said selected particles are compared to pre-established standard tracks obtained by the same process from particles of different stepped known size and enrichment ratio. <IMAGE>