Abstract: Systems and methods for detecting clandestine fissile or radioactive material on the basis of emitted radiation and particles (such as neutrons and alpha particles) arising from within the material. Emission by the fissile or radioactive material is detected in conjunction with a conventional x-ray imaging system that includes an external source of illuminating penetrating radiation, at least one detector configured to detect at least the penetrating radiation and to generate a detector signal, and a processor configured as a detector signal discriminator to generate an output indicating whether the detector signal is triggered by an origin other than illuminating penetrating radiation. Active and passive modes of detection are described by some embodiments. Other embodiments are directed toward neutron detection, gamma ray detection with energy resolution, and designs of detectors to enhance the detection of clandestine nuclear material.

Abstract: An x-ray chopper wheel assembly includes a disk chopper wheel and a source-side scatter plate that has a solid cross-sectional area that absorbs x-ray radiation and is substantially smaller than a solid cross-sectional area of the disk chopper wheel. The assembly also includes a support structure that secures the source-side scatter plate substantially parallel to the disk chopper wheel, with a source-side gap between the scatter plate and the disk chopper wheel being a distance that substantially prevents x-ray leakage. An additional, output-side scatter plate may also be provided to reduce x-ray leakage further. Embodiments enable safe operation while significantly reducing weight, which is advantageous for a variety of disk-chopper-wheel-based x-ray scanning systems, especially hand-held x-ray scanners.

Abstract: Systems and methods for detecting clandestine fissile or radioactive material on the basis of emitted radiation and particles (such as neutrons and alpha particles) arising from within the material. Emission by the fissile or radioactive material is detected in conjunction with a conventional x-ray imaging system that includes an external source of illuminating penetrating radiation, at least one detector configured to detect at least the penetrating radiation and to generate a detector signal, and a processor configured as a detector signal discriminator to generate an output indicating whether the detector signal is triggered by an origin other than illuminating penetrating radiation. Active and passive modes of detection are described by some embodiments. Other embodiments are directed toward neutron detection, gamma ray detection with energy resolution, and designs of detectors to enhance the detection of clandestine nuclear material.

Abstract: A system and corresponding method for detecting one or more high-atomic-number elements in a patient includes a Bremsstrahlung x-ray source that produces x-rays in an energy spectrum including an energy of at least 160 kiloelectron-volts (keV), a filter configured to absorb the x-rays in a region of the energy spectrum, and a collimator configured to receive the x-rays and output a collimated x-ray beam to be incident on a patient. The system and method can also include one or more collimated, energy-resolving x-ray detectors to detect fluorescent radiation emitted from the one or more high-atomic-number elements in the patient in response to the collimated x-ray beam incident on the patient. An alternative x-ray source can include a radioactive isotope. Scanning of the x-ray beam may also be performed. Embodiments enable practical clinical, in vivo measurements of lead in bone.

Abstract: A method for imaging a target with an x-ray scatter apparatus. Air scatter from air intervening between the x-ray scatter apparatus and a target overwhelms x-ray scatter from the target in that x-ray scatter from a position on the target is no more than 10% of the x-ray scatter due to intervening air scatter that reaches at least one point in the detector plane of the x-ray scatter apparatus. The target is illuminated with a beam of x-rays scanned across the target, and x-rays scattered by the target are detected using a detector with a centroid displaced with respect to the beam axis by at least five feet. The detector signal is then processed to generate an image of the target. The beam of x-rays may be unshielded, and/or the detector may be uncollimated.

Abstract: An adjustable collimator for shaping a beam of particles, such as for purposes of inspecting contents of a container. The adjustable collimator has an obscuring element substantially opaque to passage of the particles in a propagation direction that is radial with respect to the axis of rotation of a ring of apertures. A gap in the obscuring element may be characterized by a length taken along a long dimension and a jaw spacing taken along narrow dimension, and at least one of the length of the gap and the jaw spacing is subject to adjustment, either manual or automatic. The adjustable collimator may be disposed either inside or outside the ring of apertures, and, in some embodiments, the jaw spacing may be a function of distance along the long dimension relative to an edge of the gap.

Abstract: Apparatus for interrupting and/or scanning a beam of penetrating radiation, such as for purposes of inspecting contents of a container. A source, such as an x-ray tube, generates a fan beam of radiation effectively emanating from a source axis, with the width of the fan beam collimated by a width collimator, such as a clamshell collimator. An angular collimator, stationary during the course of scanning, limits the extent of the scan, and a multi-aperture unit, such as a hoop, or a nested pair of hoops, is rotated about a central axis, and structured in such a manner that the total beam fluence incident on a target is conserved for different fields of view of the beam on the target. The central axis of hoop rotation need not coincide with the source axis.

Abstract: Apparatus for interrupting and/or scanning a beam of penetrating radiation, such as for purposes of inspecting contents of a container. A source, such as an x-ray tube, generates a fan beam of radiation effectively emanating from a source axis, with the width of the fan beam collimated by a width collimator, such as a clamshell collimator. An angular collimator, stationary during the course of scanning, limits the extent of the scan, and a multi-aperture unit, such as a hoop, or a nested pair of hoops, is rotated about a central axis, and structured in such a manner that beam flux incident on a target is conserved for different fields of view of the beam on the target. The central axis of hoop rotation need not coincide with the source axis.

Abstract: An apparatus and methods for detecting radiation. A plurality of substantially parallel active collimation vanes are sensitive to the incident radiation for generating at least a first detection signal, and a rear detector detects incident radiation that passes between the substantially parallel active collimation vanes and generates a second detection signal. A processor receives and processes both the first and second detection signals. The active collimator vanes may be enclosed within a light-tight enclosure, and a first photodetector may be provided for detecting scintillation arising at the active collimation vanes, while a second photodetector may be provided for detecting scintillation arising at the rear detector.

Abstract: An apparatus for forming a beam of energetic particles and for scanning the beam of particles with respect to an inspected object. The apparatus has a source of energetic particles characterized by an effective beam origin and a rotating hoop having at least one aperture, such that the effective beam origin of the source is closer to the inspected object than the axis of rotation of the rotating hoop. A collimating structure disposed interior to the rotating hoop collimates emission by the source into a fan beam prior to impinging on the rotating hoop. In some embodiments, the effective beam origin may be moved with respect to the axis of rotation of the hoop.

Abstract: A system and methods for characterizing an inspected object on the basis of attenuation between identified regions of scattering and a plurality of detectors. An incident beam of substantially monochromatic penetrating radiation is generated by a source, which may be a radioactive source. The incident beam is characterized by a propagation axis and a source energy. Radiation scattered by the object is detected by means of a plurality of detector elements disposed about the beam of penetrating radiation, each detector element generating a detector signal characterizing a detected energy of scattered radiation. The detector signal provides for determining a displacement for each scattering point of the object relative to a fiducial position on the propagation axis of the incident beam, based upon the detected energy of the scattered radiation.

Abstract: A versatile beam scanner for generating a far-field scanned pencil beam, and, alternatively, a far-field pencil beam. An angle selector limits the angular extent of an inner fan beam emitted by a source of penetrating radiation. The source and angle selector may be translated, along a direction parallel to a central axis of a multi-aperture unit, in such a manner as to generate a scanned far-field pencil beam, when rings of apertures are interposed between the source and an inspected target, or, alternatively, a far-field fan beam, when no ring of apertures is interposed.

Abstract: Systems and methods for inspecting an object with a scanned beam of penetrating radiation. Scattered radiation from the beam is detected, in either a backward or forward direction, as is radiation transmitted through the inspected object. The source of penetrating radiation is concealed within an enclosure of a road-worthy vehicle, and detected with a large-area uncollimated detector similarly concealed within the enclosure.

Abstract: A detector and methods for producing x-ray images, more particularly based on x-rays transmitted through an inspected object. A scintillating region is translated along a path within a cross section of a beam, the cross section taken in a plane distal to the object with respect to a source of the beam. Light emitted by the scintillator region is detected, thereby generating a detection signal, the detection signal is received by a processor which generates an image signal, and an image depicting transmitted penetrating radiation is formed on the basis of the image signal.

Abstract: An apparatus for forming a beam of energetic particles and for scanning the beam of particles with respect to an inspected object. The apparatus has a source of energetic particles characterized by an effective beam origin and a rotating hoop having at least one aperture, such that the effective beam origin of the source is closer to the inspected object than the axis of rotation of the rotating hoop. A collimating structure disposed interior to the rotating hoop collimates emission by the source into a fan beam prior to impinging on the rotating hoop. In some embodiments, the effective beam origin may be moved with respect to the axis of rotation of the hoop.

Abstract: An adjustable collimator for shaping a beam of particles, such as for purposes of inspecting contents of a container. The adjustable collimator has an obscuring element substantially opaque to passage of the particles in a propagation direction that is radial with respect to the axis of rotation of a ring of apertures. A gap in the obscuring element may be characterized by a length taken along a long dimension and a jaw spacing taken along narrow dimension, and at least one of the length of the gap and the jaw spacing is subject to adjustment, either manual or automatic. The adjustable collimator may be disposed either inside or outside the ring of apertures, and, in some embodiments, the jaw spacing may be a function of distance along the long dimension relative to an edge of the gap.

Abstract: A system and method for inspecting a vehicle by means of one or more sources and detectors of penetrating radiation. The source(s) and detector(s) are carried on a mobile conveyance and deployed at a point of operation. One source swings away from the conveyance on a deployable member, such as a boom, such that the source can irradiate a vehicle from above or below. A detector deploys outwardly from the mobile conveyance, remaining mechanically coupled to the mobile conveyance in a position in a horizontal plane, such that the detector intercepts penetrating radiation from the source positioned above the inspected vehicle, which penetrating radiation has interacted with the inspected vehicle. A ramp may be provided to allow the inspected vehicle to be driven to a position between the vertically irradiating source and a transmission detector.

Abstract: Apparatus for interrupting and/or scanning a beam of penetrating radiation, such as for purposes of inspecting contents of a container. A source, such as an x-ray tube, generates a fan beam of radiation effectively emanating from a source axis, with the width of the fan beam collimated by a width collimator, such as a clamshell collimator. An angular collimator, stationary during the course of scanning, limits the extent of the scan, and a multi-aperture unit, such as a hoop, or a nested pair of hoops, is rotated about a central axis, and structured in such a manner that the total beam fluence incident on a target is conserved for different fields of view of the beam on the target. The central axis of hoop rotation need not coincide with the source axis.

Abstract: An apparatus and method for x-ray inspection of footwear while the footwear is worn on the feet of walking persons. A source of penetrating radiation, such as an x-ray tube, mounted on one side of a system, provides a fan beam of penetrating radiation contained in a substantially vertical plane, while a detector, disposed on the opposing side of the system, detects penetrating radiation that has traversed the footwear. A controller creates an image of the footwear. The system may have a sensor for detecting presence of the person and for initiating operation of the source of penetrating radiation in response thereto. The system may be installed inside a portal including a metal detector portal.

Abstract: Systems and methods for inspecting an object with a scanned beam of penetrating radiation. Scattered radiation from the beam is detected, in either a backward or forward direction, as is radiation transmitted through the inspected object. The source of penetrating radiation is concealed within an enclosure of a road-worthy vehicle, while a transmission detector is concealed within a separate enclosure.