Product Yields of ²³⁵U, ²³⁸U, ²³⁷Np, and ²³⁹Pu by Photofission Reactions with 20-, 30-, and 60-MeV Bremsstrahlung

As a basic study of photonuclear transmutation of actinides in high-level radioactive wastes using electron-produced bremsstrahlung, the absolute yields of cumulative mass distributions and the transmutation rates of²³⁵U, ²³⁸U, ²³⁷Np, and ²³⁹Pu by photofission reactions induced by 20-, 30-, and 60-MeV bremsstrahlung were measured. The results of mass yield distributions and transmutation yields agree well with other experimental results and those calculated using photofission cross sections, respectively. The transmutation efficiency per electron increases about one order of magnitude with electron energy from 20 to 60 MeV.