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

中文翻译：

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O18 + Np237反应的多核子转移通道中裂变碎片质量分布的测量

23个核的裂变碎片质量分布（${}^{234-237}\mathrm{ü}$， ${}^{236-239}p$， ${}^{238-241}普$， ${}^{240-243}\mathrm{上午}$， ${}^{242-245}\mathrm{厘米}$和 ${}^{244-246}k$）是使用多核子转移方法在 ${}^{\mathrm{18岁}}\mathrm{Ø}+{}^{237}p$，它们的激发能量依赖性最高可达70 MeV。其中，低能裂变${}^{236}p$， ${}^{238}普$和 ${}^{245}\mathrm{厘米}$是第一次报告。将所有研究核的实验数据与Langevin计算进行了比较。考虑到多机会裂变效应的计算很好地再现了峰谷比和质量非对称峰位置的分布。还讨论了赋予裂变核的角动量。