ABSTRACT

Time-sequence count data of a neutron counter were acquired at subcritical states of UTR-KINKI reactor and then a Feynman-α analysis considering delayed neutrons was carried out to determine a measured ratio of delayed to prompt neutron contribution to the correlation amplitude Y. The zero-power reactor was driven by a neutron source inherent in highly enriched uranium fuels to reduce any spatial effect. The delayed-to-prompt ratio was also calculated using several sets of delayed-neutron group parameters for thermal fission of ²³⁵U nuclide, to validate these sets by comparing with the measured ratio. The ratios calculated using Keepin’s 6-group and Spriggs’ 8-group sets agreed very well with the measured ratio. However, the ratios calculated using the other sets were almost the same as each other and in a very poor agreement with the measured ratio.

摘要

在 UTR-KINKI 反应堆的亚临界状态下获取中子计数器的时序计数数据，然后进行考虑延迟中子的 Feynman-α 分析，以确定延迟与瞬发中子对相关幅度Y的贡献的测量比率。零功率反应堆由高浓缩铀燃料中固有的中子源驱动，以减少任何空间效应。还使用多组延迟中子群参数计算了延迟-提示比，用于^{235的热裂变}核素，通过与测量的比率进行比较来验证这些集合。使用 Keepin 的 6 组和 Spriggs 的 8 组计算的比率与测量的比率非常吻合。然而，使用其他组计算的比率几乎彼此相同，并且与测量的比率非常差。