New experimental results on the symmetric fission in neutron-rich transfermium nuclei

中性子過剰超フェルミウム核の対称核分裂に関する新しい実験結果

浅井 雅人  

Asai, Masato

中性子過剰超フェルミウム核の対称核分裂に関する新しい実験結果について報告する。これらの原子核はEs標的を用いた多核子移行反応で合成し、生成した原子核はガスジェット結合型オンライン同位体分離装置で質量分離した。シリコン検出器を用いてこれらの原子核の自発核分裂片を測定し、核分裂片の質量と全運動エネルギー分布を精密に導出した。中性子過剰超フェルミウム核の対称核分裂の詳細について本実験研結果を基に議論する。

New experimental results on the symmetric fission in neutron-rich transfermium nuclei are reported. Those nuclei were produced in the multi-nucleon transfer reactions with an Es target, and reaction products were mass-separated by a gas-jet coupled on-line isotope separator at the JAEA tandem accelerator facility. Spontaneous-fission fragments of those nuclei were measured with Si detectors, and fission-fragment mass and total-kinetic-energy distributions were deduced precisely. Details of the symmetric fission in neutron-rich transfermium nuclei were discussed based on the present experimental results.