A Fast, High Light Output Scintillator for Gamma Ray and Neutron Detection

60344 The identification of fast, bright scintillators is a continual goal among scientists who design and manufacture radiation detection systems. Unfortunately, the scintillator is often the limiting technology that impedes product development and adds substantial cost. Many materials have been tried, but few can deliver both qualities. The two approaches are (1) making small incremental improvements in common scintillators or (2) studying new materials that offer greater potential. This project addresses the second route and will examine rubidium gadolinium bromide (RGB) as a versatile gamma ray and neutron sensitive detector material for a variety of scientific, industrial, and medical applications. In Phase I, several ingots of RGB were grown with differing concentrations of an activator (to stimulate light output). Single crystals, far larger than previously reported, were produced and analyzed as detectors. Both speed and light output were exemplary, with several high quality spectra recorded. The Phase II goals for producing RGB will be to increase scintillator size and optimize activator concentration. Following processing, the scintillator will be evaluated as both a gamma ray and a neutron detector. Commercial Applications and Other Benefits as described by the awardee: As a gamma ray scintillator, RGB would find use in nuclear and radiological physics as an alternative to NaI or similar scintillators where large volumes and fast timing requirements are needed. As a neutron detector, RGB could lead to a variety of new instruments for material science, neutron radiography, and nuclear security.