[3E01-04] Nuclear Data Measurement 1

[3E01] Measurement of fission-fragment mass distributions in the multinucleon transfer channels of the ¹⁸O+²³⁷Np reaction

*Katsuhisa Nishio¹, Mark James Vermeulen¹, Kentaro Hirose¹, Kun Ratha Kean^2,1, Hiroyuki Makii¹, Riccardo Orlandi¹, Kazuaki Tsukada¹, Igor Tsekhanovich³, Andrei Andreyev⁴, Shouma Ishizaki⁵ (1. JAEA, 2. TIT, 3. Bordeaux University, 4. University of York, 5. Kinki University)

Keywords:Fission-fragment mass distribution, Multinucleon transfer reaction, Multichance fission

Fission-fragment mass distributions for 23 nuclei (^234-237U, ^236-239Np, ^238-241Pu, ^240-243Am, ^242-245Cm, and^244-246Bk) were measured using the multinucleon transfer approach in the reaction ¹⁸O+²³⁷Np, and their excitation-energy dependence was obtained up to a maximum of 70 MeV. Among them, the low-energy fission of ²³⁶Np, ²³⁸Pu, and ²⁴⁵Cm 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 multichance fission well reproduced the peak-to-valley ratio and mass-asymmetry of the distribution. The angular momentum given to the fissioning nucleus is also discussed.