Measurement of (n, f ) and (n, xn) cross sections with surrogate reaction method
Measurement of (n, f ) and (n, xn) cross sections with surrogate reaction method
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使用替代反应法测量 (n, f ) 和 (n, xn) 横截面
DOI：
10.1051/epjconf/202023901007
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发表时间：
2020
影响因子：
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通讯作者：
Zuhua Liu
中科院分区：
文献类型：
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作者：
Nanru Ma;Chengjian Lin;Huiming Jia;Xinxing Xu;Feng Yang;Lei Yang;Lijie Sun;Dongxi Wang;Huanqiao Zhang;Zuhua Liu
替代反应法是克服直接测量中子感生核反应所遇到困难的重要途径。现有的替代反应一般采用非弹性激发和转移反应等外围反应，其所涉及的角动量远大于中子俘获反应，这给复合核自旋的理论修正带来了困难。我们建议用轻荷电粒子的俘获反应作为替代反应，这样两个反应中复合核的自旋分布非常相似，因此不需要进行自旋修正。在此基础上，利用236U（α，f）和（α，2n）反应作为替代反应，成功地提取了239Pu（n，f）和（n，2n）截面。与ENDFB7的数据在误差条内吻合良好，表明所提出的替代捕获反应方法的可靠性。
Surrogate reaction method is an important approach to overcome the difficulties meet in the direct measurement of neutron induced nuclear reaction. The current existing surrogate reactions generally employ the peripheral reactions such as inelastic excitation and transfer reaction where the involved angular momenta are much larger than the neutron capture reaction, which causes a difficulty in theoretical correction of spin of compound nucleus. We proposed to use capture reaction of light charged particle as the surrogate reaction, thus the spin distributions of compound nucleus in two reactions are quite similar and therefore the spin correction is not strongly desired. Based on this idea, the239Pu(n,f) and (n, 2n) cross sections were successfully extracted by using236U(α,,f) and (α, 2n) reactions as the surrogate reactions. The well coincidence of the present results with the data of ENDFB7 within the error bars shows the reliability of the proposed surrogate capture reaction method.