237Np, 238Np, 235U, 233U, and 239Pu; Fission Yield Studies

Abstract

<p> The relative cumulative yields of krypton and xenon isotopes from the thermal neutron fission of 237Np and Np238 and from the fast neutron fission of Np237 have been measured by means of a mass spectrometer. These are the first fission yield results for 238Np, and the first for 237Np at thermal neutron energies. The results are compared with those from other fissioning nuclides.</p> <p> Independent yields of the shielded nuclides 80Br, 82Br, 128I, and 130I from the thermal neutron fission of 235U, 233U, 239Pu, and 238Np have been determined by mass spectrometric analyses of the krypton and xenon β-decay products. The results are discussed in terms of conventional charge distribution theories, and also in terms of neutron emission effects.</p>