The detection and assay of fissionable material is carried out on a container known or suspected to have a material with at least one fissionable isotope. The material is irradiated with neutrons from two or more different neutron sources. The fission rates inducted at each irradiation energy are acquired with at least one neutron detector. A multispectral active neutron interrogation analysis (MANIA) is carried out to compare the detected fission rates of the neutron spectra with calculated fission rates where an iterative algorithm is carried out on a system of linear equations to solve for the isotopic composition of one or more isotopes to determine the presence, identity, and quantities of fissionable isotopes in said container.

The present specification discloses methods for inspecting an object. The method includes scanning an object in a two-step process. In the primary scan, a truck or cargo container (container) is completely scanned with a fan beam radiation, the transmitted radiation is measured with an array of detectors, and the transmission information and optionally the fission signatures are analyzed to determine the presence of high-density, high-Z and fissionable materials. If the container alarms in one or more areas, the areas are subjected to a secondary scan. This is done by precisely repositioning the container to the location of the suspect areas, adjusting the scanning system to focus on the suspect areas, performing a stationary irradiation of the areas, and analyzing the measured feature signatures to clear or confirm the presence of SNM.

An optoelectronic neutron detector and method for detecting nuclear material having a neutron capture and scatter medium receiving neutrons and producing secondary charged particles, a photodetector detecting emitted light from the secondary charged particles and outputting a detector signal, and a controller receiving the detector signal and providing an alert or quantitative indication of detected nuclear material in response to the detector signal.

A system identifying a source of radiation is provided. The system includes a radiation source detector and a radiation source identifier. The radiation source detector receives measurements of radiation; for one or more sources, generates a detection metric indicating whether that source is present in the measurements; and evaluates the detection metrics to detect whether a source is present in the measurements. When the presence of a source in the measurements is detected, the radiation source identifier for one or more sources, generates an identification metric indicating whether that source is present in the measurements; generates a null-hypothesis metric indicating whether no source is present in the measurements; evaluates the one or more identification metrics and the null-hypothesis metric to identify the source, if any, that is present in the measurements.

A neutron detector system for discriminating fissile material from non-fissile material wherein a digital data acquisition unit collects data at high rate, and in real-time processes large volumes of data directly to count neutrons from the unknown source and detecting excess grouped neutrons to identify fission in the unknown source. The system includes a Poisson neutron generator for in-beam interrogation of a possible fissile neutron source and a DC power supply that exhibits electrical ripple on the order of less than one part per million. Certain voltage multiplier circuits, such as Cockroft-Walton voltage multipliers, are used to enhance the effective of series resistor-inductor circuits components to reduce the ripple associated with traditional AC rectified, high voltage DC power supplies.

Methods and systems are disclosed for the deployment and operation of shipping container scanning systems that enables scanning of containers passing through a modern, highly automated port without impeding the flow of commerce. Locating the scanners where container dwell time is already longest, and configuring scanners to scan up to several containers in parallel but under separate scanning control, minimizes any delay associated with scanning. Operationally integrating scanning systems with the automated logistical port systems ensures smooth, delay-free operation. Controlling the flow of information so that scanning results, including but not limited to images and assessments of the presence or absence of threat material or contraband, are sent only to government Customs and/or security facilities adjacent to but separate from the port insulates port operators from involvement in activities that could slow container throughput.

Systems for landing and facilitating power flow or data transfer between an unmanned aerial vehicle (UAV) and a charging mat using a boom are described. The system includes a mat with a conductive mesh on the top and a conductive surface on the other bottom of the mat. The conductive mesh and bottom conductive surface are separated (electrically isolated) by an isolation core. The outer portion of the boom contacts part of the conductive mesh of the mat to create an electrical pathway. An inner portion of the boom penetrates through the top layer conductive mesh, through the isolating core, and contacts the bottom conductive surface of the mat to create another electrical pathway.

Methods and systems that utilize centrifugally tensioned metastable fluid detector (CTMFD) sensors and an external probing source to detect the presence of fissile and fissionable materials, including but not limited to special nuclear materials (SNMs), in containers. Such a method includes subjecting a container to probing with a fission-inducing radiation species that induces fission in an fissile or fissionable material, detecting fission neutrons emitted from the fissile or fissionable material with CTMFD sensors that each contain a detection fluid in which the fission neutrons induce cavitation in a centrifugally tensioned portion of the detection fluid. A threshold energy neutron analysis mode is then utilized to reject the radiation species and detect a fraction of the fission neutrons that have energies above a predetermined energy threshold determined by centrifugally-induced tension in the centrifugally tensioned portion of the detection fluid within each of the CTMFD sensors.

The invention is a gamma ray detector that locates a source, both horizontally and vertically. The detector comprises a tubular shield surrounded by scintillator panels. Gammas incident from one side can fully strike the scintillator facing the source, but are blocked from reaching the scintillators on the opposite side of the shield. The scintillator counting rates thus indicate the lateral direction of the source. By iteratively rotating toward the highest-counting scintillator, the detector converges to the source. An additional, central detector can be mounted within the tubular shield. When analyzed with the outer scintillators, the central detector determines the overall angular separation between the source and the detector axis, thereby locating the source in two dimensions automatically. The invention enables rapid detection and precise localization of clandestine nuclear and radiological weapons, despite shielding and clutter obfuscation, while quickly passing clean loads.

The present specification discloses methods for inspecting an object. The method includes scanning an object in a two-step process. In the primary scan, a truck or cargo container (container) is completely scanned with a fan beam radiation, the transmitted radiation is measured with an array of detectors, and the transmission information and optionally the fission signatures are analyzed to determine the presence of high-density, high-Z and fissionable materials. If the container alarms in one or more areas, the areas are subjected to a secondary scan. This is done by precisely repositioning the container to the location of the suspect areas, adjusting the scanning system to focus on the suspect areas, performing a stationary irradiation of the areas, and analyzing the measured feature signatures to clear or confirm the presence of SNM.