Abstract: A method and system for detecting special nuclear materials are disclosed. Said method and system detect the special nuclear materials by making use of the photofission characteristic and thermal neutron induced fission characteristic thereof. In one preferred embodiment, the high density and/or high atomic number region in the object to be detected is also detected first as a suspicious region.

Abstract: A method and system for detecting special nuclear materials are disclosed. Said method and system detect the special nuclear materials by making use of the photofission characteristic and thermal neutron induced fission characteristic thereof. In one preferred embodiment, the high density and/or high atomic number region in the object to be detected is also detected first as a suspicious region.

Abstract: Embodiments of the present invention disclose a nuclide identification method, a nuclide identification system, and a photoneutron emitter. The photoneutron emitter comprises: a pulsed electron accelerator configured for emitting electrons; and a photoneutron converting target configured to receive the electrons emitted by the pulsed electron accelerator and convert the electrons into photoneutrons. The photoneutron converting target has a volume of about 100 to about 8000 cm3, of about 100 to about 2500 cm3, or of about 785 cm3. These embodiments of the present invention can improve an accuracy of identification of a nuclide, and provide a practical photoneutron emitter, method and system for identifying a nuclide. Especially, these embodiments of the present invention can improve an accuracy of identification of a fissile nuclide such as 233U, 235U, and 239Pu, and provide a practical photoneutron emitter, method and system for identifying a fissile nuclide such as 233U, 235U, and 239Pu.

Abstract: The present invention provides a fast-neutron detector, comprising: a plastic scintillator array which includes at least one plastic scintillator unit, wherein sidewall surfaces of each plastic scintillator unit are covered or coated with a neutron-sensitive coating film. The fast-neutron detector based on such film-coated plastic scintillators according to the present invention advantageously addresses the mutual competition problem between a moderated volume and a measured volume in the prior art and can obtain a higher fast-neutron detecting efficiency.

Abstract: The present invention provides a cellular thermal neutron detector, comprising: a cellular structure comprised of one or more hollow regular hexagonal prism-shaped cellular units, wherein a neutron absorbing material is coated on an inner side of a pipe wall of each of the cellular units. Since the neutron-sensitive cellular structure is employed, the present invention can perform thermal neutron detection without using the scarce nuclide 3He, and effectively reduce the manufacture costs of the thermal neutron detector. Further, the present invention has characteristics such as a reduced or eliminated neutron detecting dead zone.

Abstract: A photoneutron conversion target for generating photoneutrons by directing an x-ray beam at the photoneutron conversion target includes an elongated body having a first end and a second end. When the photoneutron conversion target is in use, the x-ray beam enters the body and propagates in a direction from the first end to the second end. The body of the photoneutron conversion target is shaped such that propagation of the x-ray beam is substantially proportionate to an intensity distribution of the x-ray beam, so that the greater an intensity of x-rays of the x-ray beam, the greater the propagation distance of the x-rays within the body of the photoneutron conversion target. The photoneutron conversion target according to the invention can make full use of the x-ray beam so as to increase a yield of photoneutrons.

Abstract: A method for imaging an object by means of photoneutron transmission is provided. The method determines the position of the photoneutron rays based on the position of a neutron collimator, to overcome the problem of incapability of imaging due to loss of position information of the photoneutrons during moderation thereof. The method also images the object by arranging detector module arrays.

Abstract: The present invention provides a boron-containing gas film fast-neutron detector. The fast-neutron detector comprises a package piece having a hollow cavity; a plastic scintillator array provided in the cavity and comprising a plurality of plastic scintillator units, a gap existing between adjacent plastic scintillator units; and a boron-containing gas filled into and gas-tightly sealed in the hollow cavity, the boron-containing gas forming a boron-containing gas film in the gap between the adjacent plastic scintillator units. The fast-neutron detector of the present invention completely does not require use of scarce and expensive 3He gas, nor needs a complicated boron film coating process, improves credibility of signal coincidence, and is adapted for measurement of environment background neutrons and extensively adapted for detection of radioactive substance at sites such as customs ports, harbors and the like.

Abstract: A method and system for detecting special nuclear materials are disclosed. Said method and system detect the special nuclear materials by making use of the photofission characteristic and thermal neutron induced fission characteristic thereof. In one preferred embodiment, the high density and/or high atomic number region in the object to be detected is also detected first as a suspicious region.

Abstract: The present invention provides a boron-containing gas film fast-neutron detector. The fast-neutron detector comprises a package piece having a hollow cavity; a plastic scintillator array provided in the cavity and comprising a plurality of plastic scintillator units, a gap existing between adjacent plastic scintillator units; and a boron-containing gas filled into and gas-tightly sealed in the hollow cavity, the boron-containing gas forming a boron-containing gas film in the gap between the adjacent plastic scintillator units. The fast-neutron detector of the present invention completely does not require use of scarce and expensive 3He gas, nor needs a complicated boron film coating process, improves credibility of signal coincidence, and is adapted for measurement of environment background neutrons and extensively adapted for detection of radioactive substance at sites such as customs ports, harbors and the like.

Abstract: The present invention discloses an article inspection device, comprising: a x-ray machine, a collimation unit, a transmission detector array and at least one scattering detector array. Each of the at least one scattering detector array comprising a plurality of same scattering detector modules arranged in a matrix of i-rows and j-columns. A transmission cross section of the article transmitted by the x-rays is divided into a plurality of same sub-regions arranged in a matrix of i-rows and j-columns. The plurality of scattering detector modules arranged in i-rows and i-columns correspond to the plurality of sub-regions arranged in i-rows and j-columns one by one for detecting pair production effect annihilation photons and Compton-effect scattering photons from the respective sub-regions.

Abstract: The present invention provides a cellular thermal neutron detector, comprising: a cellular structure comprised of one or more hollow regular hexagonal prism-shaped cellular units, wherein a neutron absorbing material is coated on an inner side of a pipe wall of each of the cellular units. Since the neutron-sensitive cellular structure is employed, the present invention can perform thermal neutron detection without using the scarce nuclide 3He, and effectively reduce the manufacture costs of the thermal neutron detector. Further, the present invention has characteristics such as a reduced or eliminated neutron detecting dead zone.

Abstract: The present invention provides a fast-neutron detector, comprising: a plastic scintillator array which includes at least one plastic scintillator unit, wherein sidewall surfaces of each plastic scintillator unit are covered or coated with a neutron-sensitive coating film. The fast-neutron detector based on such film-coated plastic scintillators according to the present invention advantageously addresses the mutual competition problem between a moderated volume and a measured volume in the prior art and can obtain a higher fast-neutron detecting efficiency.

Abstract: The present invention discloses an article inspection device, comprising: an x-ray machine, a collimation unit, a transmission detector array and a scattering detector array. The scattering detector array comprising a plurality of same scattering detector modules arranged in a matrix of i-rows and j-columns. A transmission cross section of the article transmitted by the x-rays is divided into a plurality of same sub-regions arranged in a matrix of i-rows and j-columns. The plurality of scattering detector modules arranged in i-rows and j-columns correspond to the plurality of sub-regions arranged in i-rows and j-columns one by one for detecting pair production effect annihilation photons and Compton-effect scattering photons from the respective sub-regions. Obtaining atomic numbers of the respective sub-regions based on a ratio of the pair production effect annihilation photon count to the Compton-effect scattering photon count, so as to form a three-dimensional image of the article.

Abstract: A photoneutron-x ray source includes a photoneutron conversion target, which outputs both photoneutrons and x-rays simultaneously. The photoneutron-x ray source includes an x-ray generator for generating an x-ray main beam that is applied to the photoneutron conversion target. The photoneutron conversion target generates photoneutrons upon the application of the x-ray main beam to the photoneutron conversion target. The photoneutron conversion target has a body that defines a passageway extending through the body and that is structured such that a first x-ray beam of the x-ray main beam can pass through the passageway without any reaction with the body, while a second x-ray beam of the x-ray main beam can enter the body and react with the body to emit the photoneutrons.

Abstract: A method and a system for contraband detection in an object using photoneutrons and x-rays includes an x-ray generator that generates an x-ray main beam including a first x-ray beam and a second x-ray beam, the first x-ray beam being directed to pass through the object. A photoneutron conversion target is arranged to receive the second x-ray beam so as to generate photoneutrons, the photoneutrons being directed to enter the object and react with the object to emit characteristic ?-rays. An x-ray detecting arrangement is arranged to receive the first x-ray beam that has passed through the object in order to perform x-ray imaging detection of the detected object. A ?-ray detecting arrangement is arranged to receive the characteristic ?-rays in order to perform neutron detection of the object based on the characteristic ?-rays. The x-ray imaging detection and the neutron detection are simultaneously performed.

Abstract: A method for imaging an object by means of photoneutron transmission is provided, which comprises the steps of: collimating the photoneutron rays passing through the object by means of a neutron collimator so as to determine the position information of the photoneutron rays based on the position of the neutron collimator; detecting the collimated photoneutron ray beams by means of a detector module, wherein the detector module includes a neutron moderator and at least one thermal neutron detector located within the neutron moderator, wherein the neutron moderator converts the photoneutrons into thermal neutrons, and wherein the thermal neutron detector measures the thermal neutrons so as to obtain attenuation information of the photoneutron ray beams upon passing through the object; and integrating the position information and the attenuation information so as to form an image of the corresponding part of the object.

Abstract: The present invention discloses an article inspection device, comprising: an x-ray machine, a collimation unit, a transmission detector array and a scattering detector array. The scattering detector array comprising a plurality of same scattering detector modules arranged in a matrix of i-rows and j-columns. A transmission cross section of the article transmitted by the x-rays is divided into a plurality of same sub-regions arranged in a matrix of i-rows and j-columns. The plurality of scattering detector modules arranged in i-rows and j-columns correspond to the plurality of sub-regions arranged in i-rows and j-columns one by one for detecting pair production effect annihilation photons and Compton-effect scattering photons from the respective sub-regions. Obtaining atomic numbers of the respective sub-regions based on a ratio of the pair production effect annihilation photon count to the Compton-effect scattering photon count, so as to form a three-dimensional image of the article.

Abstract: The present invention discloses an article inspection device, comprising: a x-ray machine, a collimation unit, a transmission detector array and at least one scattering detector array. Each of the at least one scattering detector array comprising a plurality of same scattering detector modules arranged in a matrix of i-rows and j-columns. A transmission cross section of the article transmitted by the x-rays is divided into a plurality of same sub-regions arranged in a matrix of i-rows and j-columns. The plurality of scattering detector modules arranged in i-rows and i-columns correspond to the plurality of sub-regions arranged in i-rows and j-columns one by one for detecting pair production effect annihilation photons and Compton-effect scattering photons from the respective sub-regions.

Abstract: A method and system for detecting special nuclear materials are disclosed. Said method and system detect the special nuclear materials by making use of the photofission characteristic and thermal neutron induced fission characteristic thereof. In one preferred embodiment, the high density and/or high atomic number region in the object to be detected is also detected first as a suspicious region.