Research Of Explosive Detection Based On Multi-Energy X-Ray

Correctly identifying the explosive in the baggage and parcel is a very urgent need in the security work at the main entrance and exit of the station, airport and so on. X-ray technology is the most widely used technology in the security system at home and abroad. With the development of the high resolution photon counter, it is possible to apply the multi-energy X-ray to security inspection.In this paper, we first introduce the various interaction of X-ray with matter, focus on the photoelectric effect and the Compton scattering theory.The relationship between the linear attenuation coefficient of the material, the equivalent atomic number of the material and the photon energy is pointed out, as well as the relationship between the Compton scattering attenuation coefficient of the material, electron dense of the materialand photonic energy, which will be as the theoretical basis of the experiments in this paper.Experiments use a X-ray source and two high-resolution detectors which are used to capture the photon intensity after the attenuation of material absorption and the occurrence of Compton scattering. Through some relevant algorithms we can calculate the transmission attenuation curve and Compton scattering attenuation curveof the material, it will be a basis for material identification.In addition, for packaging material detection, under the premise of known packaging material properties (its transmission attenuation curve),a mathematical model for calculating the transmission attenuation and scattering attenuation curves is proposed, and an optimization method is proposed to solve these two mathematical models.Experiments about the transmission,firstly, several common organic compounds and different concentrations of the solution are used as the experimental samples, which confirme that the resolving power of the experimental system is greater than that of the conventional dual energy system. Then the test tube and scale are used as packing material, and the results are compared with the direct measurement,which verify the accuracy of this method.On the Compton scattering experiments,first of all, the glass, wood and paraffin are used as the experimental samples. The experimental results are compared with real electron density of each material. The results show that the system can successfully obtain information in the electron density of the test substance. In addition, the water and alcohol in the test tube are separated from the experimental effective area, and several kinds of organic compounds are also successfully identified.The experimental results show that this method is effective for material identification as well as matter detection with packaging, can be applied to the detection of explosives.