Experimental fission study using multi-nucleon transfer reactions

Nishio, Katsuhisa   ; Hirose, Kentaro  ; Lguillon, R.*; Makii, Hiroyuki   ; Orlandi, R.  ; Tsukada, Kazuaki  ; Smallcombe, J.*; Chiba, Satoshi*; Aritomo, Yoshihiro*; Tanaka, Shoya*; Otsuki, Tsutomu*; Tsekhanovich, I.*; Petrache, C. M.*; Andreyev, A. N.

The objective of this work is to extend fission data for actinide nuclei not investigated so far in order to understand the fission mechanism, especially for neutron-rich nuclei. Multi-nucleon transfer reactions were used to populate the compound nuclei which cannot be accessed by particle capture or fusion reactions. The experiment was carried out at the tandem facility of Japan Atomic Energy Agency. In the multi-nucleon transfer reactions using O beam, a wide variety of nuclei around a target nucleus was produced. By identifying transfer channels, fission data of nuclei more than fifteen compound nuclei were generated in one experiment. Another feature of transfer reaction is that the excitation energies of a compound nucleus can be populated continuously from the ground state up to several tens MeV, allowing us to study the excitation energy dependence of fission properties. From the excitation function of fission probabilities, fission-barrier heights of neutron-rich actinide nuclei were obtained. Experiments were carried out in the reactions of O + U, Th, Cm, Np. The obtained fission fragment mass distributions were reproduced by a model calculation based on a fluctuation dissipation model.