NUCLEAR-PHYSICAL CHARACTERISTICS OF NEPTUNIUM ISOTOPES
V.G. Khlopin Radium Institute, Leningrad 197022, USSR
A survey is given of the work carried out at the Radium Institute on studying the nuclear-physical properties of neptunium that influence the work of nuclear power installations. There are presented the measured cross-sections of the reaction 237Np(n,2n), giving rise to the short-lived isomer 236Np(s), at En=7+15 MeV and on 252Cf spontaneous fission neutrons, the cross-sections of 237Np, 236Np(s) and the long-lived isomer 236Np(l), by thermal neutrons and the respective resonance fission integrals, the cross-sections of 236Np(l) fission by neutrons in the energy range En = 0.0253 eV + 20 keV, the partial half-life of 235Np in relation to alpha radiation. New data are given on the cross-sections of reactions 238U(p,xn)Np at Ep=7+30 MeV applied for production of neptunium isotopes and plutonium-236.
KEYWORDS: neptunium, isomer, neutrons, reactions, fission, cross-section