A large-area directional radiation detection system useful in detecting shielded radiological weapons may include a large number of prism-shaped detectors stacked in a two-dimensional array of particle detectors in which alternate detectors are displaced frontward and rearward in, for example, a checkerboard-type arrangement of detectors. If a source of radiation is in front of the array, the frontward detectors act as collimators for the rearward detectors, thereby producing a narrow detection peak among the rearward detectors. The lateral position of the detection peak indicates the lateral position of the source, and the width of the detection peak indicates the distance of the source from the detector array, thereby providing a three-dimensional determination of the source location. The high detection efficiency and large solid angle of the detector array enable rapid detection of even well-shielded threat sources at substantial distances, while simultaneously determining the positions of the detected sources.

Methods and systems for detecting nuclear material concealed within an enclosure are provided. An ionized air density is measured at one or more locations outside of the enclosure. The presence of the concealed nuclear material is detected, for each of the one or more locations, based on a characteristic of the measured ionized air density indicative of concealed nuclear materials.

Methods of detecting high atomic weight materials in a volume such as a truck or cargo container are disclosed. The volume is scanned with an X-ray imaging system and a muon detection system. Using the output data of the muon detection system, the exit momentum and incoming and outgoing tracks of each muon are reconstructed. A muon scattering statistical model is calculated using the muon exit momentum and the incoming and outgoing tracks of the muon. A most likely scattering density map is determined according to the muon-scattering statistical model and an X-ray statistical model. A visual representation of the most likely scattering density map is displayed.

Disclosed is a directional gamma ray or neutron detector that locates a source both horizontally and vertically. In some embodiments, the detector comprises four rod scintillators around a shield, and an orthogonal panel scintillator mounted frontward of the rod scintillators. The azimuthal angle of the source may be calculated according to the detection rates of the rod scintillators, while the polar angle of the source may be calculated from the panel scintillator rate using a predetermined angular correlation function. Thus, the exact location of the source can be found from a single data set without iterative rotations. Embodiments of the detector enable rapid detection and precise localization of clandestine nuclear and radiological weapons in applications ranging from hand-held survey meters and walk-through portals, to vehicle cargo inspection stations and mobile area scanners. Such detectors are needed to detect clandestine nuclear weapons worldwide.

A detector assembly includes a hollow body in which a printed circuit board, a resistive plate, a drilled board, a drift volume, and a cathode are disposed. A surface of the printed circuit board exposed to the resistive plate includes printed circuit lines for measuring first and second coordinates of a charge event. The hollow body can include a sealable opening to remove contaminants outgassed from one or more components of the detector assembly and to fill the hollow body with an operational gas. The sealable opening can be fluidly coupled to a gas and vacuum system to reduce the concentration of the outgassed contaminants.

A method and an apparatus for distinguishing radionuclides are disclosed. The method comprises the steps of: receiving energy generated in one or more radioactive elements; applying energy as a weight for each channel to spectrum of the received energy; and distinguishing the one or more radioactive elements on the basis of the spectrum of the spectrum to which the weight is applied. A radioactive element having an energy value corresponding to a peak value of the spectrum of the energy to which the weight is applied, as an energy value of a Compton edge, is distinguished as the one or more radioactive elements. According to the present invention, it is possible to more accurately monitor radiation even while using a plastic scintillator, and further to improve energy resolution of a plastic scintillator.

According to one general aspect, an apparatus may include a plurality of sensors configured to detect a presence of a source of radiation. The apparatus may include a garment configured to be worn by a user. The garment may include a plurality of tactile feedback devices configured to automatically indicate to the user, without intervention by the user, a direction of the source of radiation.

A device configured to detect particles from a radioactive source can localize the source in two dimension, such as the azimuthal and polar angles of the source. Embodiments of the device may comprise a hollow cylindrical or tubular array of side detector panels, plus a central detector positioned within the array, with no shield or collimator. The various side detector counting rates can indicate the azimuthal angle of the source, while the polar angle can be determined by a ratio of the side detector data divided by the central detector data. Embodiments of the directional detector device can provide greatly improved inspections, thereby detecting clandestine nuclear and radiological weapons, or other sources that are to be localized, rapidly and precisely.

Disclosed is a directional gamma ray or neutron detector that locates a source both horizontally and vertically. In some embodiments, the detector comprises four rod scintillators around a shield, and an orthogonal panel scintillator mounted frontward of the rod scintillators. The azimuthal angle of the source may be calculated according to the detection rates of the rod scintillators, while the polar angle of the source may be calculated from the panel scintillator rate using a predetermined angular correlation function. Thus, the exact location of the source can be found from a single data set without iterative rotations. Embodiments of the detector enable rapid detection and precise localization of clandestine nuclear and radiological weapons in applications ranging from hand-held survey meters and walk-through portals, to vehicle cargo inspection stations and mobile area scanners. Such detectors are needed to detect clandestine nuclear weapons worldwide.

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.