This work presents measurements of the half-lives of excited nuclear states of ²³⁷Np and ⁵⁷Fe using a liquid scintillation (LS) spectrometer and a gamma detector. A novel approach for the determination of the half-lives of some excited states is presented which uses only LS counting data from a detector with two PMTs. The lifetime of the 1st and 2nd excited states of ⁵⁷Fe were obtained without the use of a gamma detector. The obtained value for the 59.54 keV level of ²³⁷Np is 67.60(25) ns. The obtained values for the 14.4 keV and 136.5 keV levels of ⁵⁷Fe are 97.90(40) ns and 8.780(36) ns, respectively. The half-life results from this study are consistent with the average value found in the reference decay data tables and have a lower uncertainty.

这项工作展示了使用液体闪烁 (LS) 光谱仪和伽马探测器测量²³⁷ Np 和⁵⁷ Fe的激发核态的半衰期。提出了一种确定某些激发态半衰期的新方法，该方法仅使用来自具有两个 PMT 的检测器的 LS 计数数据。⁵⁷ Fe的第一和第二激发态的寿命是在不使用伽马探测器的情况下获得的。²³⁷ Np的 59.54 keV 水平获得的值为67.60(25) ns。获得的 14.4 keV 和 136.5 keV 水平的值为⁵⁷Fe 分别为 97.90(40) ns 和 8.780(36) ns。本研究的半衰期结果与参考衰减数据表中的平均值一致，不确定性较低。