Abstract: A method and computer program software product for establishing an areal density of an elemental constituent of one layer of a stack of layers of material overlying a substrate. Incident penetrating radiation excites characteristic x-ray fluorescent radiation in multiple lines associated with each of one or more elements. Areal densities of successive layers are determined by self-consistent solution of equations relating the ratios of intensities of the characteristic fluorescence lines of successive elements.

Abstract: An inspection system based upon an enclosed conveyance such as a van, capable of road travel, for inspecting persons or objects. The conveyance is characterized by an enclosing body, or skin. A source of penetrating radiation and a spatial modulator for forming the penetrating radiation into a beam, both contained entirely within the body of the enclosed conveyance, irradiate the person or object with a time-variable scanning profile. A detector module generates a scatter signal based on the scatter of penetrating radiation. A proximity sensor may be employed to generate a relative motion signal based on a relative disposition of the conveyance and the inspected object. An image is formed of the contents of the object based in part on the scatter signal and the relative motion signal. A detector, which may be separate or part of the scatter detector module, may exhibit sensitivity to decay products of radioactive material.

Abstract: A method and computer program software product for establishing an areal density of an elemental constituent of one layer of a stack of layers of material overlying a substrate. Incident penetrating radiation excites characteristic x-ray fluorescent radiation in multiple lines associated with each of one or more elements. Areal densities of successive layers are determined by self-consistent solution of equations relating the ratios of intensities of the characteristic fluorescence lines of successive elements.

Abstract: Two or more high-frequency microphones are used to determine where an individual spark or other excitation beam strikes a sample in an optical emission spectroscopy (OES) instrument. The position of the spark can be correlated with the elemental composition of the material in the sample vaporized by the spark. The microphones are placed appropriately in air around a sparker of the instrument, or appropriately on the sample, or on both the sample and in the air. Arrival times of sound from the spark to the microphones, or a difference in the arrival times, yields information, from which the position of the spark relative to the microphones, and hence the absolute position of the spark, is deduced, such as by triangulation. Optionally or in addition, a signal that indicates a time when the spark is produced is correlated with one or more spectra detected by a spectrometer, so a spectrum that results from the vaporized sample can be distinguished from a spectrum that results from heated gas above the sample.

Abstract: A system for inspecting an enclosure. A source generates a beam of penetrating radiation that is characterized, at each instant of time, by a power spectrum of intensity as a function of energy. A first module conveys the source along the length of the enclosure while a detector, coupled so as to move in coordination with the first module, detects the beam of penetrating radiation after the beam interacts with the object and generating a detector signal. A beam shaper modifies the instantaneous power spectrum of the beam of penetrating radiation. The first module and the detector may be coupled by a gantry straddling the enclosure. Other modules may be coupled to move with the first module.

Abstract: An inspection system based upon an enclosed conveyance such as a van, capable of road travel, for inspecting objects of inspection that may include persons. The conveyance is characterized by an enclosing body, or skin. A source of penetrating radiation and a spatial modulator for forming the penetrating radiation into a beam, both contained entirely within the body of the enclosed conveyance, irradiate an object with a time-variable scanning profile. A detector module generates a scatter signal based on penetrating radiation scattered by contents of the object, while a proximity sensor generates a relative motion signal based on a relative disposition of the conveyance and the inspected object. An image is formed of the contents of the object based in part on the scatter signal and the relative motion signal. A detector, which may be separate or part of the scatter detector module, may exhibit sensitivity to decay products of radioactive material.

Abstract: A system and method for inspecting an object, the system and method comprising a source for generating a penetrating radiation beam for irradiating the object, the beam having, for each instant of time, an instantaneous energy spectrum of intensity, a shaper for modulating the generated beam, thereby creating a shaped beam, the shaper comprising at least a first section and a second section, the first section attenuating the intensity of a portion of the generated beam by a first attenuation factor and the second section attenuating the intensity of another portion of the generated beam by a second attenuation factor, and at least one detector for detecting the shaped beam after the shaped beam interacts with the object. The source may scan a beam across an object while the source and at least one detector are moving on a platform capable of highway travel or on an inspection module movable with respect to the object.

Abstract: A radiation shield and method for reducing ambient radiation levels at a distance from a surface irradiated by penetrating radiation emanating from an instrument. The shield attaches to an end of the instrument abutting an irradiated surface and has a platen of attenuating material disposed within a plane substantially transverse to the propagation direction of penetrating radiation and substantially adjacent to the irradiated surface.

Abstract: An x-ray inspection system for identifying fissile material includes one or more sources of penetrating radiation that generate first, second, and third instantaneous spectra where the object is exposed to the second only if there is no penetration of the first and the object is exposed to the third only if there is no penetration of the second. Further, the sources of the second and the third spectra are pulsed. Consequently, ambient levels of radiation may be held below cabinet levels while identifying objects containing fissile material.

Abstract: Some embodiments of the invention are directed toward systems and methods of detecting clandestine nuclear material in the form of emitted radiation and particles (e.g., neutrons and alpha particles). These embodiments, which may be used in conjunction with a conventional x-ray imaging system, may include an external source of penetrating radiation, at least one detector configured to detect at least 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 backscattered 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 apparatus for selective radiation detection includes a neutron detector that facilitates detection of neutron emitters, e.g. plutonium, and the like; a gamma ray detector that facilitates detection of gamma ray sources, e.g., uranium, and the like; and/or an X-ray analyzer that facilitates detection of materials that can shield radioactive sources, e.g., lead, and the like.

Abstract: An inspection system based upon an enclosed conveyance such as a van capable of road travel. The conveyance is characterized by an enclosing body, or skin. The system has a source of penetrating radiation contained entirely within the body of the enclosed conveyance and a spatial modulator for forming the penetrating radiation into a beam for irradiating an object with a time-variable scanning profile. A detector module generates a scatter signal based on penetrating radiation scattered by contents of the object, while a proximity sensor generates a relative motion signal based on a relative disposition of the conveyance and the inspected object. An image is formed of the contents of the object based in part on the scatter signal and the relative motion signal. A detector, which may be separate or part of the scatter detector module, exhibits sensitivity to decay products of radioactive material.

Abstract: A radiation shield and method for reducing ambient radiation levels at a distance from a surface irradiated by penetrating radiation emanating from an instrument. The shield attaches to an end of the instrument abutting an irradiated surface and has a platen of attenuating material disposed within a plane substantially transverse to the propagation direction of penetrating radiation and substantially adjacent to the irradiated surface.

Abstract: A device and method for identifying the composition of a target sample. The target sample may be a matrix such as a metal alloy, a soil sample, or a work of art. The device includes an x-ray fluorescence detector that produces an x-ray signal output in response to the target sample. The device also includes an optical spectroscope that produces an optical signal output in response to the target sample. Further, a processor is included that analyzes and combines the x-ray signal output and the optical signal output to determine the composition of the test material. In one embodiment, the optical spectroscope is a laser induced photon fluorescence detector.

Abstract: An x-ray fluorescence analyzer and method. The analyzer and method use a single radio-active source, such as, 241Am to determine the composition of a metal alloy or precious metal. The method compensates for Rayleigh scattering by first determining a scaling factor using a particular energy line in the spectrum of the test material and comparing that line to the same energy line for a pure metal. Based on the scaling factor the energy spectrum for the pure is compensated and then subtracted from the energy spectrum of the test material at discrete points.

Abstract: An inspection system based upon an enclosed conveyance such as a van, capable of road travel, for inspecting objects of inspection that may include persons. The conveyance is characterized by an enclosing body, or skin. A source of penetrating radiation and a spatial modulator for forming the penetrating radiation into a beam, both contained entirely within the body of the enclosed conveyance, irradiate an object with a time-variable scanning profile. A detector module generates a scatter signal based on penetrating radiation scattered by contents of the object, while a proximity sensor generates a relative motion signal based on a relative disposition of the conveyance and the inspected object. An image is formed of the contents of the object based in part on the scatter signal and the relative motion signal. A detector, which may be separate or part of the scatter detector module, may exhibit sensitivity to decay products of radioactive material.

Abstract: A system and method for inspecting an enclosure with penetrating radiation. Radiation side-scattered from an object within the enclosure is detected, allowing the object to be located. If the object is deemed suspect, a volume element of the suspect object is further irradiated with penetrating radiation, and radiation coherently-scattered by the volume element is detected. The energy spectrum and angular distribution of the coherently-scattered radiation are used to characterize the volume element of the suspect object.

Abstract: An apparatus and method for detecting neutrons, particularly, with directional sensitivity. The apparatus is a detector with a scintillator containing high neutron-capture-cross-section atoms for capturing neutrons and emitting electromagnetic radiation, and an optical detector for detecting the emitted electromagnetic radiation and for generating an electrical signal. The high neutron-capture-cross-section atoms may be gadolynium, in particular, and the detector may additionally have a moderator for converting fast neutrons into thermal neutrons that are then captured by the high neutron-capture-cross-section atoms.

Abstract: A system for inspecting the contents of a container is provided. The system includes a first source for emitting sequential beams of penetrating electromagnetic radiation from a target in a first set of substantially parallel directions, a conveyor for moving the container relative to the first source, a first detector for detecting the penetrating radiation after interaction with the contents of the container and generating a first set of signals corresponding to each of the substantially parallel directions and a controller for characterizing the contents of the container based at least on the first set of signals. The first detector may be a scatter detector. Similarly, the first detector may be a transmission detector.

Abstract: A system and method for inspecting an object, the system and method comprising a source for generating a penetrating radiation beam for irradiating the object, the beam having, for each instant of time, an instantaneous energy spectrum of intensity, a shaper for modulating the generated beam, thereby creating a shaped beam, the shaper comprising at least a first section and a second section, the first section attenuating the intensity of a portion of the generated beam by a first attenuation factor and the second section attenuating the intensity of another portion of the generated beam by a second attenuation factor, and at least one detector for detecting the shaped beam after the shaped beam interacts with the object. The source may scan a beam across an object while the source and at least one detector are moving on a platform capable of highway travel or on an inspection module movable with respect to the object.