Provided herein are neutron imaging systems (e.g., radiography and tomography) systems and methods that provide, for example, high-quality, high throughput 2D and 3D fast or thermal neutron and/or X-ray images. Such systems and methods find use for the commercial-scale imaging of industrial components. In certain embodiments, provided herein are system comprising a plurality of independent neutron absorber-lined collimators (e.g., 4 or more collimators) extending outwards from a central neutron source assembly.

The systems, devices, and processes described herein may identify a beam of a voice-controlled device that is directed toward a reflective surface, such as a wall. The beams may be created by a beamformer. An acoustic echo canceller (AEC) may create filter coefficients for a reference sound. The filter coefficients may be analyzed to identify beams that include multiple peaks. The multiple peaks may indicate presence of one or more reflective surfaces. Using the amplitude and the time delay between the peaks, the device may determine that it is close to a reflective surface in a direction of the beam.

Provided herein are systems and methods for generating a plurality of different monoenergetic neutron energies using a plurality of interchangeable ion beam targets. In certain embodiments, each of the plurality of ion beam targets is configured to generate a monoenergetic energy value that is at least 100 kiloelectron volts (keV) different from the other ion beam targets. In some embodiments, the ion beam targets are composed of LiF, TiT.sub.1-2, ErD.sub.1.5, ErT, or Li.

Provided herein are systems and methods for generating a plurality of different monoenergetic neutron energies using a plurality of interchangeable ion beam targets. In certain embodiments, each of the plurality of ion beam targets is configured to generate a monoenergetic energy value that is at least 100 kiloelectron volts (keV) different from the other ion beam targets. In some embodiments, the ion beam targets are composed of LiF, TiT.sub.1-2, ErD.sub.1.5, ErT, or Li.

Provided herein are systems, devices, articles of manufacture, and methods for generating neutrons employing a high energy ion beam target (HEM target) and a target backing configured to be in contact with the bottom surface of the HEIB target (e.g., to generate an ion beam target assembly). In certain embodiments, the HEM target has a thickness that is less than the penetration depth of protons or deuterons in the high energy ion beam that strikes the target. In certain embodiments, the target backing comprises a high hydrogen diffusion metal (e.g., palladium), has open spaces dispersed throughout for reduced proton diffusion distances, and has a shape and thickness such that all, or virtually all, of the protons or deuterons that pass through the HEIB target are stopped. Also provided herein are systems, devices, and methods for changing targets in an ion beam accelerator system.

Systems and methods for use of a proton beam or a negative hydrogen ion beam cyclotron for production of a flux of a neutron beam and its use in investigation of material analysis is provided. The methods, apparatuses and uses include positioning a target material for irradiation on a sample holder, focusing a proton ion beam or a negative hydrogen ion beam from the cyclotron to the target material; irradiating the target material to induce a proton-neutron reaction thereby producing a flux of a neutron beam; transmitting the flux of the neutron beam through a neutron spectrum modulator, focusing the flux of the neutron beam to a sample material thereby producing a radiation emission; and detecting the radiation emission using a detector.

Systems and methods for use of a proton beam or a negative hydrogen ion beam cyclotron for production of a flux of a neutron beam and its use in investigation of material analysis is provided. The methods, apparatuses and uses include positioning a target material for irradiation on a sample holder, focusing a proton ion beam or a negative hydrogen ion beam from the cyclotron to the target material; irradiating the target material to induce a proton-neutron reaction thereby producing a flux of a neutron beam; transmitting the flux of the neutron beam through a neutron spectrum modulator, focusing the flux of the neutron beam to a sample material thereby producing a radiation emission; and detecting the radiation emission using a detector.

Radiating device (1) comprising at least one vacuum chamber (2), an electrostatic accelerator or laser of high power and high frequency (5) for producing at least one primary beam inside the vacuum chamber (2), and an active material layer (4) carried by a support (3) into the vacuum chamber (2) to generate an intense neutron flux when the active layer is struck by the primary beam, and at least one target (6) comprising a material, with the target (6) disposed on the same side of the electrostatic accelerator or power laser (5) as the active material layer (4).

A neutron generator includes an ion source disposed in a pressurized environment containing an ionizable gas. The ion source includes a substrate with a bundle of carbon nanotubes extending therefrom. The ends of the nanotubes are spaced from a grid. Ion source voltage supply circuitry supplies a positive voltage potential between the substrate and the grid of the ion source to cause ionization of the ionizable gas and emission of ions through the grid. An ion accelerator section is disposed between the ion source and a target. The ion accelerator section accelerates ions that pass through the grid towards the target such that collisions of the ions with the target cause the target to generate and emit neutrons therefrom. The ion source, accelerator section and target are housed in a sealed tube and preferably the carbon nanotubes of the bundle are highly ordered with at least 10.sup.6 carbon nanotubes per cm.sup.2 that extend in a direction substantially parallel to the central axis of the tube. The neutron generator provides gas ionization at much higher atomic to molecular ratio that the prior art, which allows for small compact size designs suitable for logging tools that are used in space-constrained downhole environments.

A neutron generator includes an ion source disposed in a pressurized environment containing an ionizable gas. The ion source includes a substrate with a bundle of carbon nanotubes extending therefrom. The ends of the nanotubes are spaced from a grid. Ion source voltage supply circuitry supplies a positive voltage potential between the substrate and the grid of the ion source to cause ionization of the ionizable gas and emission of ions through the grid. An ion accelerator section is disposed between the ion source and a target. The ion accelerator section accelerates ions that pass through the grid towards the target such that collisions of the ions with the target cause the target to generate and emit neutrons therefrom. The ion source, accelerator section and target are housed in a sealed tube and preferably the carbon nanotubes of the bundle are highly ordered with at least 10.sup.6 carbon nanotubes per cm.sup.2 that extend in a direction substantially parallel to the central axis of the tube. The neutron generator provides gas ionization at much higher atomic to molecular ratio that the prior art, which allows for small compact size designs suitable for logging tools that are used in space-constrained downhole environments.