High-Yield Pulsed Neutron Generator

A pulsed neutron generator is proposed for the detection of special nuclear material. A recently developed RF-excited plasma neutron generator will be pulsed to produce the activating neutrons whose pulse length is 100 microseconds with a fall time of less than 1 microsecond. High pulse repetition rates and high peak neutron yields can be otained depending upon the RF generator used. Using the T-T nuclear reaction, a novel emission geometry and an ideal acceleration voltage, the expected neutron energy will be less than 8.5 MeV to prevent the emission of interfering gamma-ray lines from other materials. In Phase I an existing neutron generator will be pulsed to produce the desired neutron-pulse time structure and a high peak yield. The present deuterium generator will be redesigned to support the safe use of tritium. The proposed system will be designed to be low cost, and mechanically and electronically robust, to ensure its wide distribution and use at ports throughout the world. Unlike penning diode sources the generator is expected to have a long lifetime. The project has a high probability of success based on the recent development by Adelphi and Lawrence Berkeley National Laboratory of a new RF plasma neutron generator.