Abstract: A long-range method and a system for reliably detecting and identifying special nuclear materials is provided that relies on the emission of delayed neutrons present in the decay of fission products (delayed neutron precursors) as a unique signature for the special nuclear materials, such as highly enriched uranium (235/238U). The method relies on a time-of-flight measurement in the first 1 ?s after the inducing radiation pulse, and pulse height data analysis for both neutrons and gamma rays that can be done at a much higher data rate than in traditional pulse processing systems. The thermal neutron fission within the time regime of 100-500 ?s provides a unique signature of special nuclear materials such as the highly enriched uranium.

Abstract: A long-range method and a system for reliably detecting and identifying special nuclear materials is provided that relies on the emission of delayed neutrons present in the decay of fission products (delayed neutron precursors) as a unique signature for the special nuclear materials, such as highly enriched uranium (235/238U). The method relies on a time-of-flight measurement in the first 1 ?s after the inducing radiation pulse, and pulse height data analysis for both neutrons and gamma rays that can be done at a much higher data rate than in traditional pulse processing systems. The thermal neutron fission within the time regime of 100-500 ?s provides a unique signature of special nuclear materials such as the highly enriched uranium.

Abstract: The present invention includes a high-energy detector having a cathode chamber, a support member, and anode segments. The cathode chamber extends along a longitudinal axis. The support member is fixed within the cathode chamber and extends from the first end of the cathode chamber to the second end of the cathode chamber. The anode segments are supported by the support member and are spaced along the longitudinal surface of the support member. The anode segments are configured to generate at least a first electrical signal in response to electrons impinging thereon.

Abstract: The present invention includes a high-energy detector having a cathode chamber, a support member, and anode segments. The cathode chamber extends along a longitudinal axis. The support member is fixed within the cathode chamber and extends from the first end of the cathode chamber to the second end of the cathode chamber. The anode segments are supported by the support member and are spaced along the longitudinal surface of the support member. The anode segments are configured to generate at least a first electrical signal in response to electrons impinging thereon.