Formation of heavy neutron-deficient nuclides in 3He-induced reactions

• Published in: Bulletin of the Russian Academy of Sciences. Physics 2015-07, Vol.79 (7), p.848-851
• Main Authors: Aaltonen, J., Gromova, E. A., Jakovlev, V. A., Helariutta, K., Maltsev, N. A., Penttilä, H., Rubchenya, V. A., Trzaska, W. H., Salminen-Paatero, S.
• Format: Article
• Language: English
• Subjects: 2014: Fundamental Problems of Nuclear Physics; Atomic Energy; Hadrons; Heavy Ions; Nuclear Physics; Nuclear Technologies” (LXIV International Meeting on Nuclear Spectroscopy and the Structure of Atomic Nuclei); Physics; Physics and Astronomy; Proceedings of the International Conference “Nuclei
• ISSN: 1062-8738; 1934-9432
• DOI: 10.3103/S1062873815070047

Reactions of 3 He with actinide nuclei are a promising tool for the production of heavy neutrondeficient nuclei, which are of great interest as tracers in environmental studies. In this work, highly enriched 235 U targets 1 mg cm –2 thick were irradiated using 3 He ions with energies of 20.4–42.0 MeV at the Accelerator Laboratory of University of Jyväskylä, Finland. The irradiated targets were analyzed with gamma and alpha spectrometers and then dissolved in order to chemically separate Pu and Np from the fission products and the target material. The chemical yields of 234 Np and 236 Pu were determined by measuring their activities prior to and after chemical separation. Previously unknown excitation functions of the nuclides 234, 236, 237 Pu and 234, 235, 236 m Np were thus found. The obtained experimental data were analyzed using the direct reaction theory for a model with nuclear friction included in the fission channel and due consideration of the preequilibrium processes.