Production of 235Np, 236Pu and 237Pu via nuclear reactions on 235,236,238U and 237Np targets

Abstract

Summary A summary of methods for cyclotron production of 235Np (396.1d), 236Pu (2.858y) and 237Pu (45.2d) via nuclear reactions with protons and 3He-ions on 235,236,238U and 237Np targets in wide energy ranges is given. Methods for the chemical separation and purification of these nuclides from the irradiated uranium and neptunium targets are described. Cross sections, yields and radionuclidic purities of 235Np, 236Pu and 237Pu are presented and compared with literature data on the nuclear reactions leading to these radionuclides. The nuclear reactions with the so far highest known yields of 235Np, 236Pu and 237Pu are determined: 236U(p,2n) 235Np, 237Np(p,2n+pnβ -) 236Pu and 237Np(p,n) 237Pu, respectively. The highest radionuclidic purity of 235Np, 236Pu and 237Pu tracers can be reached with the 236U(p,2n) 235Np, 236U(p,nβ -) 236Pu and 237Np(3He,t) 237Pu reactions, respectively. In addition new cross sections and yield data of the 236U(3He,p3n) 235Np reaction in the energy range 42.4–60 MeV are given.