Large detection area, high spatial resolution, high dynamic range and low noise neutron detectors are disclosed. Curved detectors that minimize parallax errors and boundary regions without sacrificing its intrinsic resolution or the efficiency are also disclosed.

Large detection area, high spatial resolution, high dynamic range and low noise neutron detectors are disclosed. Curved detectors that minimize parallax errors and boundary regions without sacrificing its intrinsic resolution or the efficiency are also disclosed.

A fissile neutron detection system includes a neutron moderator and a neutron detector disposed proximate such that a majority of the surface area of the neutron moderator is disposed proximate the neutron detector. Fissile neutrons impinge upon and enter the neutron moderator where the energy level of the fissile neutron is reduced to that of a thermal neutron. The thermal neutron may exit the moderator in any direction. Maximizing the surface area of the neutron moderator that is proximate the neutron detector beneficially improves the reliability and accuracy of the fissile neutron detection system by increasing the percentage of thermal neutrons that exit the neutron moderator and enter the neutron detector.

A fissile neutron detection system includes an ionizing thermal neutron detector arrangement including an inner peripheral shape that at least substantially surrounds a moderator region for detecting thermal neutrons that exit the moderator region but is at least generally transparent to the incident fissile neutrons. A moderator is disposed within the moderator region having lateral extents such that any given dimension that bisects the lateral extents includes a length that is greater than any thickness of the moderator arrangement transverse to the lateral extents. The moderator can include major widthwise and major lengthwise lateral extents such that any given dimension across the lengthwise and widthwise lateral extents includes a length that is greater than any thickness of the moderator arrangement transverse to the lateral extents.

A slow neutron detection device is disclosed, comprising: a first slow neutron converter and a second slow neutron converter, and a readout electrode wire set and cathode wire sets arranged between the first slow neutron converter and the second slow neutron converter. By arranging a readout circuit between the two slow neutron converters, an electron drift distance is reduced by half without changing a dimension of the detection device, and an average over-threshold probability of a signal is increased.

A slow neutron detection device is disclosed, comprising: a first slow neutron converter and a second slow neutron converter, and a readout electrode wire set and cathode wire sets arranged between the first slow neutron converter and the second slow neutron converter. By arranging a readout circuit between the two slow neutron converters, an electron drift distance is reduced by half without changing a dimension of the detection device, and an average over-threshold probability of a signal is increased.

A narrow thermal neutron detector includes a slidably receivable ionization thermal neutron detector module within an overall housing body. An active sheet layer of the ionization thermal neutron detector module can be tensioned across its width. The ionization thermal neutron detector module can include module upper major surface extents and module lower surface extents such that, when installed within the housing body, the module upper major surface extents are in a first spaced apart confronting relationship with housing upper major surface extents to define a first clearance and module lower major surface extents are in a second spaced apart confronting relationship with housing lower major surface extents to define a second clearance to accommodate housing flexing due to ambient pressure change. The housing body can be formed with a single opening for receiving the ionization thermal neutron detection module or with opposing first and second opposing end openings.

A narrow thermal neutron detector includes a slidably receivable ionization thermal neutron detector module within an overall housing body. An active sheet layer of the ionization thermal neutron detector module can be tensioned across its width. The ionization thermal neutron detector module can include module upper major surface extents and module lower surface extents such that, when installed within the housing body, the module upper major surface extents are in a first spaced apart confronting relationship with housing upper major surface extents to define a first clearance and module lower major surface extents are in a second spaced apart confronting relationship with housing lower major surface extents to define a second clearance to accommodate housing flexing due to ambient pressure change. The housing body can be formed with a single opening for receiving the ionization thermal neutron detection module or with opposing first and second opposing end openings.

A narrow thermal neutron detector includes a slidably receivable ionization thermal neutron detector module within an overall housing body. An active sheet layer of the ionization thermal neutron detector module can be tensioned across its width. The ionization thermal neutron detector module can include module upper major surface extents and module lower surface extents such that, when installed within the housing body, the module upper major surface extents are in a first spaced apart confronting relationship with housing upper major surface extents to define a first clearance and module lower major surface extents are in a second spaced apart confronting relationship with housing lower major surface extents to define a second clearance to accommodate housing flexing due to ambient pressure change. The housing body can be formed with a single opening for receiving the ionization thermal neutron detection module or with opposing first and second opposing end openings.

A boron coated straw detector for use in a neutron detection system is disclosed comprising a boron coated straw having at least one boron-coated septum radially oriented and extending a pre-determined distance towards the center of the straw. Preferably, the straw comprises a plurality of septa comprising a rigid surface, coated on both sides with a boron composition. Preferably, the septa run the length of the straw detector from one end of the straw to the other. The area coated on the septa adds to the area coated on the arc segments offering a significant benefit in sensitivity of the neutron detector.