Method and apparatus for detecting, locating, and analyzing chemical compounds using subatomic particle activation
申请人:——
公开号:US20030165212A1
公开(公告)日:2003-09-04
An apparatus and method for detecting, locating, and analyzing chemical compounds located within a test subject using subatomic particle activation. In a first embodiment, an excitation source excites a target to simultaneously produce beams each consisting of certain subatomic species, for example fast neutrons and alpha particles. The test subject (and chemical compounds contained therein) is irradiated by the fast neutrons, thereby stimulating the emission of prompt gamma rays. Gamma and alpha detectors are positioned relative to the test subject and target(s) so as to detect the emitted prompt gamma rays and alpha particles in substantial coincidence, and the known physical relationship between the beams is used to spatially locate the activated chemical compound. Energy spectra derived from the gamma detectors are filtered to eliminate all non-relevant spectral artifacts, thereby 1) permitting the creation of a plurality of parallel coincidence channels; 2) reducing the subsequent signal processing required; and 3) increasing the overall accuracy and efficiency of the chemical compound identification and analysis processes. In a second embodiment, thermal neutron-induced gamma emissions are detected and analyzed in conjunction with the fast neutron-induced gammas to provide a warning signal of the possible presence of certain types of contraband. A multi-beam/multi-target embodiment is also disclosed for more accurate spatial location. A method for calibrating and evaluating the efficacy of the system under varying test parameters is further disclosed.
一种利用亚原子粒子活化技术检测、定位和分析位于测试对象体内的化合物的仪器和方法。在第一个实施方案中,激发源激发目标,同时产生由特定亚原子种类(例如快中子和阿尔法粒子)组成的光束。测试对象(及其所含化合物)受到快中子的辐照,从而激发瞬时伽马射线的发射。伽马射线和α粒子探测器相对于测试对象和目标物进行定位,以便检测到发射的瞬时伽马射线和α粒子是否完全重合,并利用光束之间的已知物理关系对活化的化合物进行空间定位。从伽马探测器得到的能谱经过过滤,以消除所有无关的光谱伪影,从而:1)允许创建多个并行的重合通道;2)减少所需的后续信号处理;3)提高化合物识别和分析过程的整体准确性和效率。在第二个实施方案中,热中子诱发伽马辐射与快中子诱发伽马辐射一起检测和分析,以提供可能存在某些类型违禁品的警告信号。还披露了一种多波束/多目标实施方案,用于更精确的空间定位。还披露了在不同测试参数下校准和评估系统功效的方法。