Neutron imaging systems and methods

Abstract

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.

We claim: 
     
         1 . A system comprising:
 a collimator with an opening for collecting neutrons; and   a neutron trap/diffuser positioned at the opening of the collimator,   wherein the neutron trap/diffuser includes a hollowed section to promote migration of neutrons towards the opening of the collimator, and   wherein the neutron trap/diffuser includes a solid section made from a moderating material.   
     
     
         2 . The system of  claim 1 , further comprising a neutron source. 
     
     
         3 . The system of  claim 1 , wherein the collimator is conical or pyramidal. 
     
     
         4 . The system of  claim 3 , wherein the neutron trap/diffuser is tapered at a same or similar slope as the collimator. 
     
     
         5 . The system of  claim 1 , wherein the neutron trap/diffuser is straight. 
     
     
         6 . The system of  claim 1 , wherein the neutron trap/diffuser is inverted such that the neutron trap/diffuser grows larger as it moves towards the neutron source. 
     
     
         7 . The system of  claim 1 , wherein the collimator has a variable diameter or length that allows for the length-to-diameter ratio (L/D) to be varied, resulting in variable image resolution and image capture time. 
     
     
         8 . The system of  claim 1 , further comprising a moderator assembly, wherein the neutron trap/diffuser is positioned within the moderator assembly. 
     
     
         9 . The system of  claim 1 , wherein the neutrons comprise thermal neutrons. 
     
     
         10 . The system of  claim 1 , further comprising a multiplier assembly to provide for additional neutrons. 
     
     
         11 . The system of  claim 1 , wherein the collimator is a neutron absorber-lined collimator. 
     
     
         12 . The system of  claim 1 , wherein the collimator is one of a plurality of independent collimators extending outwards from the neutron source, wherein each of plurality of independent collimators is configured to produce a neutron imaging beam line. 
     
     
         13 . The system of  claim 12 , wherein the neutron trap/diffuser is one of a plurality of neutron trap/diffusers, each positioned at an opening of one of the plurality of independent collimator. 
     
     
         14 . The system of  claim 1 , further comprising a neutron imaging detector, wherein the neutron imaging detector comprising a detector medium and an imaging plane. 
     
     
         15 . The system of  claim 14 , further comprising neutron focusing and/or reflecting elements that are configured to increase neutron flux at the imaging plane. 
     
     
         16 . The system of  claim 1 , wherein the collimator is a neutron absorber-lined collimator. 
     
     
         17 . A method of neutron imaging comprising:
 positioning an object in front of a neutron imaging detector;   generating source neutrons with a neutron source assembly;   collecting a portion of the source neutrons with a collimator to produce a neutron imaging beam line; and   passing the neutron imaging beam through at least a portion of the object thereby generating a neutron image that is collected by the neutron imaging detector.   
     
     
         18 . The method of  claim 17 , wherein collecting the portion of the source neutrons with the collimator further includes collecting the portion of the source neutrons with a neutron trap/diffuser positioned at the opening of the collimator. 
     
     
         19 . The method of  claim 17 , further comprising moderating the source neutrons with a moderator assembly. 
     
     
         20 . The method of  claim 17 , further comprising inserting and removing the object to be image with an automated object movement system, and further comprising inserting and removing an imaging media of the neutron imaging detector with the automated object movement system.