In a general aspect, a collimator system is described. In some aspects, a neutron beam collimation method includes receiving a neutron beam from a neutron source; polarizing the neutron beam using a polarizer, and obtaining a collimated neutron beam from the polarized neutron beam. The neutron beam generated by the neutron source has a first beam divergence and includes a plurality of neutrons. The collimated neutron beam has a second beam divergence that is less than the first beam divergence. Obtaining the collimated neutron beam includes mapping transverse momentum of each respective neutron, of the plurality of neutrons, onto a polarization degree of freedom of the respective neutron by applying a sequence of phase shift gradients to the polarized neutron beam, and after applying the sequence of phase shift gradients, passing the polarized neutron beam through an analyzer.

The object of the invention relates to a neutron source, which contains a proton accelerator for producing a proton beam, and a target arranged in the trajectory of the proton beam exiting the proton accelerator for producing a neutron beam, to which the proton beam arrives in long, typically 0.5 ms-3 ms impulses, and contains a moderator-reflector system arranged in the vicinity of the target and serving for producing a moderated neutron beam, which has at least one moderator, and a reflector surrounding the moderator and the target, characterized by that at least one statistical neutron chopper is arranged to protrude into the at least one moderated neutron beam exiting channel that modulates at least one neutron beam intensity according to a random or pseudo-random sample as a function of time with its neutron transmittance ability varying according to such pattern.

The object of the invention relates to a neutron source, which contains a proton accelerator for producing a proton beam, and a target arranged in the trajectory of the proton beam exiting the proton accelerator for producing a neutron beam, to which the proton beam arrives in long, typically 0.5 ms-3 ms impulses, and contains a moderator-reflector system arranged in the vicinity of the target and serving for producing a moderated neutron beam, which has at least one moderator, and a reflector surrounding the moderator and the target, characterized by that at least one statistical neutron chopper is arranged to protrude into the at least one moderated neutron beam exiting channel that modulates at least one neutron beam intensity according to a random or pseudo-random sample as a function of time with its neutron transmittance ability varying according to such pattern.

A first system for producing a high flux of neutrons for non-destructive testing includes a dense plasma focus device neutronically coupled to a subcritical or sub-prompt critical fission assembly. The dense plasma focus device is a source of initiating neutrons for the fission assembly, and the fission assembly is configured to multiply a number of the initiating neutrons via inducing fission. A second system for producing a high flux of neutrons includes a gas-target neutron generator neutronically coupled to a subcritical or sub-prompt critical fission assembly. The gas-target neutron generator is a source of initiating neutrons for the fission assembly, and the fission assembly is configured to multiply a number of the initiating neutrons via inducing fission.

A first system for producing a high flux of neutrons for non-destructive testing includes a dense plasma focus device neutronically coupled to a subcritical or sub-prompt critical fission assembly. The dense plasma focus device is a source of initiating neutrons for the fission assembly, and the fission assembly is configured to multiply a number of the initiating neutrons via inducing fission. A second system for producing a high flux of neutrons includes a gas-target neutron generator neutronically coupled to a subcritical or sub-prompt critical fission assembly. The gas-target neutron generator is a source of initiating neutrons for the fission assembly, and the fission assembly is configured to multiply a number of the initiating neutrons via inducing fission.

A beam target for generating a nuclear reaction product by irradiation with a beam obtained from a beam generation source includes a cone body which has a tapered inner surface which is reduced in diameter toward a tip, and supply means for supplying liquid metal to the inner surface of the cone body to form a liquid film of the liquid metal on the inner surface. It is possible to form the liquid film of the liquid metal on a cone body surface to increase an irradiation area of the beam, and also dispose a target substance such as LLFP around the cone body, and hence it is possible to efficiently use the nuclear reaction product (e.g., a neutron) generated by beam irradiation of the liquid metal.

A beam target for generating a nuclear reaction product by irradiation with a beam obtained from a beam generation source includes a cone body which has a tapered inner surface which is reduced in diameter toward a tip, and supply means for supplying liquid metal to the inner surface of the cone body to form a liquid film of the liquid metal on the inner surface. It is possible to form the liquid film of the liquid metal on a cone body surface to increase an irradiation area of the beam, and also dispose a target substance such as LLFP around the cone body, and hence it is possible to efficiently use the nuclear reaction product (e.g., a neutron) generated by beam irradiation of the liquid metal.

A novel thin-film target can the life of tritium targets for the production of 14 MeV neutrons by the .sup.3H(.sup.2H,n).sup.4He nuclear reaction while using only a small fraction of the amount of tritium compared to a standard thick-film target. With the thin-film target, the incident deuterium is implanted through the front tritide film into the underlying substrate material. A thin permeation barrier layer between the tritide film and substrate reduces the rate of tritium loss from the tritide film. As an example, good thin-film target performance was achieved using W and Fe for the barrier and substrate materials, respectively.

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.

A system and method for performing active scanning on a nuclear fuel rod are provided. The system includes an electrically-driven neutron generator including an ion source, an accelerator, and a target; a moderator surrounding the neutron generator and configured to moderate neutrons generated by the neutron generator; a fuel rod channel disposed within the moderator, the fuel rod channel configured to receive a nuclear fuel rod and subject the nuclear fuel rod to a predetermined neutron flux; and a plurality of radiation detectors. When the nuclear fuel rod is subjected to the predetermined neutron flux, neutrons induce a secondary radiation of prompt and delayed gamma emissions, neutron emission, or a combination thereof that are detected by the plurality of radiation detectors to determine an amount of fissile material in the nuclear fuel rod and a spatial distribution of the fissile material along a length of the nuclear fuel rod.