Novel Neutron Detector for High Rate Imaging Applications

65611 Next generation neutron science facilities, such as the Spallation Neutron Source, require improved thermal neutron detectors with high counting rate capability, high spatial resolution, low cost per unit area, and adaptability to unique geometries. This project will develop a rugged, low-cost thermal neutron detection technology using a large array of straw detector elements, each with a very thin converter coating, that can be produced and assembled efficiently and economically. The small diameter of individual straws will permit good spatial resolution and adaptable size and configuration. Assembling the straws into modules, and using modern integrated circuit technology, will allow the straws to be read out individually in parallel, thereby permitting extremely high count rates. In Phase I, single straw neutron detectors of 10 cm and 1 m length, as well as a 50-straw module, were successfully constructed and shown to demonstrate stable operation. Experimental testing of gamma ray discrimination, neutron efficiency, aging effects, and spatial resolution was performed with excellent results, including longitudinal resolution approaching 5 mm in a 1 m detector and sensitivity exceeding that of commonly used He3 detectors. In Phase II, cost effective methods for base materials production will be developed. A rugged module housing and two electronics readout systems will be designed, constructed, and evaluated. Testing at neutron facilities will be performed to demonstrate the functionality of the detector for various applications, and the results of this testing will be used to refine and produce a fully functional detector with accompanying electronics. Commercial Applications and Other Benefits as described by the awardee: The proposed neutron detector should have application in neutron scattering facilities at government and university nuclear research laboratories in the U.S. and abroad. Enhanced neutron scattering capabilities should enable progress in materials characterization and structural biology, resulting in advancements in biotechnology, the aviation and automobile industries, and superconductivity research, among other fields. A rugged, low-cost neutron detector also should provide more practical and lower cost technology for neutron survey applications