Applications of Boron Loaded Scintillating Fibers as NDA Tools for Nuclear211 Safeguards

摘要

Nuclear safeguards and nonproliferation rely on nondestructive analytical tools211u001efor prompt and noninvasive detection, verification, and quantitative analysis of 211u001enuclear materials in demanding environments. A new tool based on the detection of 211u001ecorrelated neutrons in narrow time windows is being investigated to fill the 211u001eniche created by the current limitations of the existing methods based on 211u001epolyethylene moderated (sup 3)He gas proportional tubes. Commercially produced 211u001eBoron-loaded ((sup 10)B) plastic scintillating fibers are one such technology 211u001eunder consideration. The fibers can be configured in a system to have high 211u001eefficiency, short neutron die-away, pulse height sensitivity, and mechanical 211u001eflexibility. Various configurations of the fibers with high density polyethylene 211u001ehave been considered which calculationally result in high efficiency detectors 211u001ewith short die-away times. A discussion of the design considerations and 211u001ecalculations of the detector efficiency, die-away time, and simulated pulse 211u001eheight spectra along with preliminary test results are presented.