Detection of nuclear materials: Features and functions of effective half-life

作者：Liu Su-ping^*; Hu Guang-chun; Wu Huai-long; Chu Cheng-sheng; Liu Zhao; Zeng Jun; Xiang Qing-pei; Ding Ge

来源：Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment , 2014, 735: 480-484.

DOI：10.1016/j.nima.2013.09.032

• Nuclear material
• Fissile material detection
• Effective half-life
• Nondestructive detection

The delayed high-energy gamma ray method is an approach used to detect the presence of nuclear materials. To study the features and functions of the effective half-life (EHL) in this method, a scenario where a beam of 14 lVleV neutrons is used to irradiate a pure U-238 indefinitely thin target was assumed. In this work, a population for study was built, consisting of the seven fission products that are the dominant contributors to the beta-delayed gamma rays with energies above 3 MeV. Based on this population for study, calculations were performed to trace the decay of the integral intensity of the gamma rays above 3 MeV for a variety of beam on intervals, to study the EHL at a variety of beam off intervals, and to investigate the features and functions of the EHL. The study showed that the EHL has a feature that means that any measured EHL should fall within an appropriate range if nuclear material is present. Because of this feature, the EHL can be used as complementary evidence to confirm the presence of nuclear materials, on the precondition that a 'clear' spectral region of interest can be settled upon.

• 出版日期2014-1-21
• 单位中国工程物理研究院; 中国工程物理研究院核物理与化学研究所