Surrogate reactions are a powerful tool to access neutron-induced reaction cross sections of short-lived nuclei. However, to infer neutron-induced reaction cross sections from measured deexcitation probabilities requires a consistent and rigorous theoretical framework describing both charged-particle and neutron-induced reactions. This work presents the first practical application of the new approach developed in O. Bouland, Phys. Rev. C 100, 064611 (2019) to Pu fissile isotopes, Pu*. Average neutron-induced reaction cross sections and deexcitation probabilities measured in surrogate reactions are simultaneously analyzed with an efficient Monte Carlo -matrix-extended theory algorithm using a unique set of nuclear-structure parameters to describe both observables. Fission probabilities allow one to estimate fission-barrier heights, not otherwise accessible in fissile isotopes. The theoretical framework is here extended to model 'giant' resonance structures observed in the fission probabilities of some nuclides. A careful study of the impact of the uncertainties on nuclear parameters and on the populated compound system angular distribution has been carried out. This study raises questions on the normalization of some fission probabilities measured in the 70's in () reactions, that could not have been pointed out without the use of the here-presented complex technique. This finding is especially important for the peculiar Pu* system. In addition, our study reveals for the Pu* compound system a 10 to 30% too high value of the only-performed low-energy neutron-induced fission cross section measurement (Gerasimov , JINR-E–3-97-213 (1997)) and, subsequently of the evaluated fission cross section below 50 keV for the Pu.

中文翻译：

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首次同时评估 Pu 裂变同位素的裂变概率和中子诱导截面

替代反应是获取短寿命核的中子诱导反应截面的有力工具。然而，要从测量的去激发概率推断中子诱发反应截面，需要一个一致且严格的理论框架来描述带电粒子和中子诱发反应。这项工作首次展示了物理学家 O. Bouland 开发的新方法的实际应用。Rev. C 100, 064611 (2019) 为 Pu 裂变同位素，Pu*。通过有效的蒙特卡罗矩阵扩展理论算法，使用一组独特的核结构参数来描述这两个可观测值，同时分析替代反应中测量的平均中子诱导反应截面和去激发概率。裂变概率使人们能够估计裂变势垒的高度，这是裂变同位素无法通过其他方式获得的。这里的理论框架被扩展到模拟在某些核素的裂变概率中观察到的“巨大”共振结构。对不确定性对核参数和填充复合系统角分布的影响进行了仔细研究。这项研究对 70 年代在 () 反应中测量的一些裂变概率的归一化提出了问题，如果不使用此处介绍的复杂技术，就不可能指出这一点。这一发现对于特殊的 Pu* 系统尤其重要。此外，我们的研究表明，对于 Pu* 化合物系统，唯一执行的低能中子诱发裂变截面测量值过高了 10% 到 30%（Gerasimov，JINR-E–3-97-213 (1997) ），以及随后评估的 Pu 裂变截面低于 50 keV。