Measurement of fission-fragment mass distributions in the multinucleon transfer channels of the O+Np reaction

O+Np多核子移行反応を用いた核分裂片質量数分布の測定

Vermeulen, M. J.; 西尾 勝久   ; 廣瀬 健太郎  ; Kean, K. R.; 牧井 宏之   ; Orlandi, R.  ; 塚田 和明  ; Tsekhanovich, I.*; Andreyev, A. N.; 石崎 翔馬*; 奥林 瑞貴*; 田中 翔也*; 有友 嘉浩*

Vermeulen, M. J.; Nishio, Katsuhisa; Hirose, Kentaro; Kean, K. R.; Makii, Hiroyuki; Orlandi, R.; Tsukada, Kazuaki; Tsekhanovich, I.*; Andreyev, A. N.; Ishizaki, Shoma*; Okubayashi, Mizuki*; Tanaka, Shoya*; Aritomo, Yoshihiro*

Fission fragment mass distributions for 23 nuclei (U, Np, Pu, Am, Cm, and Bk) were measured using the multi-nucleon transfer approach in the reaction of O+Np, and their excitation-energy dependence was obtained up to a maximum of 70 MeV. Among them, the low energy fission of Np, Pu, and Cm is reported for the first time. The experimental data for all the studied nuclei were compared to the Langevin calculations. The calculation which takes into account the effects of multi-chance fission well reproduced the peak-to-valley ratio and mass-asymmetric peak positions of the distributions. The angular momenta given to the fissioning nucleus is also discussed.