Measurement of yields and angular distributions ofγ-quanta from the interaction of 14.1 MeV neutrons with oxygen,phosphorus,and sulfur

A study of the inelastic scattering of neutrons with an energy of 14.1 MeV on the nuclei of oxygen,phosphorus,and sulfur was performed at the TANGRA facility at JINR(Dubna).The experiment aimed to refine existing data and obtain new data on the yields and angular distributions ofγ-quanta emitted by the studied nuclei due to neutron-induced nuclear reactions using the tagged neutron method.Two types of detector systems were used to registerγ-quanta.Theγ-ray yields were measured using a high-purity germanium(HPGe)detector.The angular distributions ofγ-rays were obtained using a system of 18 scintillation detectors based on bismuth germanite Bi_(4)Ge_(3)O_(12)(BGO)located around the sample.The performed experiments measured the yields of two transitions for the reaction of tagged neutrons with 16O,nine transitions for the reaction with ^(31)P,and nine transitions for the reaction with ^(32)S for the first time.The angular anisotropy of theγ-radiation accompanying the inelastic scattering of neutrons with an energy of 14.1 MeV on ^(31)P nuclei was also measured for the first time.

标记中子法检测包裹内爆炸物

利用标记中子方法（Tagged Neutron Method,TNM）对爆炸物进行检测可以降低本底、确定被检物位置,是国际上较早研究、目前也得到重视的一种方法。和通常的快中子检测手段相比,其可以降低本底200~300倍,可大大提高系统的信噪比,提高检测精度,减小测量时间。相比一般的爆炸物检测装置采用固定模式,论文介绍一种可移动式检测装置,包括其系统设计,探测器选取,标样的制备与检测,常见的两种爆炸物（TNT、硝铵）模拟物制备,系统整机测试等,并对系统测试结果进行分析,给出相应的改进建议。

标记中子法检测墙体内爆炸物

介绍了标记中子法检测墙体内爆炸物的检测方法。通过时间谱的精细选择,对特定时间窗内!谱进行分析,将C、N、O等主要元素的特征谱进行精确计算和测量,利用序贯分析解决高密度墙体干扰、特征峰区分困难问题。对10 cm和15 cm厚墙体后面放置300 g硝铵、TNT炸药模拟样品进行探测,检测时间最长为10 min,正确检出率可达到80%以上。