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7495542 
Meetings & Symposia 
IEC-based neutron generator for security inspection system 
Miley, GH; Stubbers, R; Wu, L 
2003 
924-929 
English 
Neutron activation including Thermal Neutron Analysis (TNA) and Fast Neutron Analysis (FNA) are powerful methods for detecting certain types of explosives in luggage/cargoes. A Cylindrical Converging Inertial Electrostatic Confinement (RC-IEC) device provides a unique method to provide dual energy neutrons and x-rays for such inspections. As an accelerator plasma-target device, the IEC is simpler, can be switched on or off, and can reliably produce neutrons and x-rays with minimum maintenance. In an IEC, a high voltage grid (cathode), at ∼80kV, is located in a grounded vacuum vessel (anode). A plasma discharge is formed between the grid and wall using low pressure D gas (or D-T). The grid then extracts and accelerates ions towards the centerline. The converging ion beams form a high-density plasma along the center axis, and continued ion bombardment of this "target" creates fusion neutrons (2.5 MeV for D-D fusion or 14.7 MeV for D-T). The IEC also offers a dedicated x-ray source by reversing the polarity of the electrodes and using either hydrogen or a noble gas fill. In this paper, we discuss the way to improve the neutron yield from the CR-IEC, and describe a conceptual inspection system, which includes a RC-IEC neutron/x-ray generator array, a detector array, and corresponding controllers. A fuzzy logic control/analysis system is proposed to obtain an optimal interpolation of the combined signals with minimum interrogation time.