We present experimental and MCNP modeled results of neutron flux monitoring in an irradiator, which consists of a²⁵²Cf sealed source housed in the center of a cubic block of high-density polyethylene. This work is contributing to our development in the delayed gamma-ray spectroscopy non-destructive assay technique for nuclear safeguards and security applications. We evaluated the thermal and resonance flux values using the Westcott foil activation method for two measurement position count rates of ¹⁹⁷Au and ¹¹⁵In. Comparisons between the calculated thermal fluxes from measurements and those from MCNP models show deviations of ~20%. However, both the measured and modeled thermal fluxes are two orders of magnitude higher than the fluxes at the resonance peak energies at both measurement positions, demonstrating that the irradiator is sufficient. Furthermore, this work showed that with a²⁵²Cf sealed source of a strength of 4.4 × 10⁶ n.s⁻¹, a thermal flux in the range 2–5 × 10⁴ n.s⁻¹.cm⁻² is achievable in our compact irradiator making it suitable for active analysis techniques such as DGS.

我们介绍了在辐照器中中子通量监测的实验结果和MCNP建模结果，该辐照器由一个²⁵² Cf的密封源组成，该源位于高密度聚乙烯立方块的中心。这项工作为我们在用于核保障和安全应用的延迟伽马光谱无损分析技术方面的发展做出了贡献。我们使用Westcott箔活化方法评估了¹⁹⁷ Au和¹¹⁵两个测量位置计数率的热通量和共振通量值在。从测量值计算得出的热通量与从MCNP模型获得的热通量之间的比较表明，偏差约为20％。但是，测量和建模的热通量都比两个测量位置的共振峰能量处的通量高两个数量级，这表明辐照器是足够的。此外，这项工作表明，使用强度为4.4×10 ⁶ ns ^-1的²⁵² Cf密封源，在我们的紧凑型辐射器制造中，热通量可以达到2–5×10 ⁴ ns ^-1 .cm ^-2。它适用于DGS等主动分析技术。