Improved Identification of illicit materials using an X-ray backscattering technique

该项目的目的是展示可以在X射线后向散射技术方面取得的潜在改进，以便更好地识别货物/行李中的非法走私材料。通过将对X射线散射过程的详细了解和蒙特卡罗模拟与多能X射线源和新的高效率、高分辨率CZT探测器的实验结果相结合，将实现该项目的可能性。目前最先进的商业X射线背向散射货物扫描系统利用低Z(原子序数)有机材料产生的增加的散射来识别违禁品。目前系统中使用的探测器只能测量散射X射线的强度。然而，高后向散射强度的区域，通常与违禁品(毒品、烟草、塑料炸药和货币)有关，可以被确定为X射线图像中较亮的区域。这种相当基本的有机/无机分离通常是唯一可用的信息。到目前为止，这被认为足以识别不符合其清单并需要人工检查的板条箱。这一过程造成了延误，一些板条箱被不必要地打开。

The aim of this project is to demonstrate the potential improvements that can be made in X-ray backscattering techniques to better identify illicitly smuggled material in cargo / baggage. The possibilities of this project will be achieved by combining a detailed understanding of the X-ray scattering processes and Monte-Carlo modelling with experimental results from poly-energetic X-ray sources and new high-efficiency, high-resolution CZT detectors. Current state-of-the-art commercial X-ray backscatter cargo scanning systems make use of the increased scatter that results from low-Z (atomic number) organic materials to identify contraband items. The detectors used in current systems are only capable of measuring the intensity of scattered X-rays. However, areas of high-backscatter intensity, typically associated with contraband (drugs, tobacco, plastic explosives & currency), can be established as brighter regions in an X-ray image. This rather basic level of organic/inorganic separation is usually the only information available. To date, this has been considered sufficient to identify crates which don't meet their manifest and require human inspection. This process creates delays and some crates are unnecessarily opened.