Critical Dimensions Of Aqueous Solutions Of U(37)O2F2

The critical dimensions of a sphere of an aqueous solution of 37-wt%-{sup 235}U-enriched uranyl fluoride and of several unreflected and water-reflected cylinders at a number of chemical concentrations were determined experimentally. The critical uranium concentration in the unreflected sphere was 51.93 g/liter. The neutron multiplication factor of the sphere was calculated by the DSN transport code in the S{sub 4} approximation to be 1.0100; the relative fission-rate distribution along a diameter, also calculated by DSN, compared favorably with measurements. The results from the cylinders, although less detailed and less accurate, can be generalized for nuclear criticality safety guidance. The dimensions of equivalent spheres, infinite cylinders, and infinite slabs were estimated for selected chemical concentrations by equating bucklings

Critical Dimensions Of Aqueous Solutions Of U(37)O2F2

The critical dimensions of a sphere of an aqueous solution of 37-wt%-{sup 235}U-enriched uranyl fluoride and of several unreflected and water-reflected cylinders at a number of chemical concentrations were determined experimentally. The critical uranium concentration in the unreflected sphere was 51.93 g/liter. The neutron multiplication factor of the sphere was calculated by the DSN transport code in the S{sub 4} approximation to be 1.0100; the relative fission-rate distribution along a diameter, also calculated by DSN, compared favorably with measurements. The results from the cylinders, although less detailed and less accurate, can be generalized for nuclear criticality safety guidance. The dimensions of equivalent spheres, infinite cylinders, and infinite slabs were estimated for selected chemical concentrations by equating bucklings

CRITICALITY EXCURSION OF NOVEMBER 10, 1961

A criticality excursion occurred at the Oak Ridge Critical Experiments Laboratory on November l0, l961 as enriched uranium metal, neutron reflected and moderated by hydrogen, was being assembled. It is estimated that the energy yield was between 10/sup 15/ and 10/sup 16/ fissions. There was no personnel exposure or property damage. Fission product contamination, both airborne and contained in the metal, decayed sufficiently overnight to allow unhindered continuation of the experiment. The excursion was caused by a too rapid approach of the two sections of uranium constituting the experiment. (auth