AbstractA technique based on the response differences of enriched 6Li and 7Li glass scintillators has been developed for the real time measurement of the tritium production rate from the 6Li isotope in an experimental breeder blanket of a D—T fusion reactor. The effectiveness of the method is dependent on the degree to which the scintillation responses of two glasses can be matched for all interactions arising from the neutron and gamma fields within the assembly. However, the energy resolution of the scintillation pulses contains a component that is dependent on the composition of the glass which cannot be compensated for either electronically or analytically. The glasses used must therefore be carefully selected to ensure that the difference between their intrinsic scintillation resolutions is minimal.This paper describes measurements of the scintillation energy resolution for a range of commercially available glasses as a function of energy for electrons, protons, deuterons, and alpha particles. The results showed that systematic errors in the measurement of tritium breeding from 6Li, using the proposed technique, are minimized if the glasses of different lithium enrichment have the same chemical composition. Analysis of the results indicated that for optimum accuracy the total lithium content of the glasses should be small (about 2%).
'Burning plasma' diagnostics for the physics of JET and ITER