Optimization of a neutron image plate detector with low γ-sensitivity

Recent experimental studies on new materials (storage phosphors and neutron converter) to be used in a low gamma-sensitive neutron image plate detector have been performed at the Research Center Julich and Darmstadt University of Technology. It was shown that a mixture LiF + KCl: Eu2+ (or KBr:Eu2+) features a higher neutron/gamma signal ratio compared to BaFBr:Eu2+ mixed with Gd as in commercially available neutron image plates. However, the smaller neutron capture cross-section of Li-6 in comparison with Gd requires the use of significantly thicker recording layers. This article presents the results of numerical estimations for the performance of such a detector. The use of image plates with a thick recording layer and a regular cell structure allowing for the increase in spatial resolution (pixelated image plate) is discussed. (C) 2004 Elsevier B.V. All rights reserved.