MEASUREMENTS OF FUSION NEUTRON INDUCED ACTIVATION AND DECAY HEAT IN RHENIUM.COMPARISON WITH CODE PREDICTIONS

摘要

Tungsten is a common material used whenrnheavy thermal flux load must be supported. ThernInternational Thermonuclear Experimental Reactorrn(ITER) will make use of large quantities of Tungsten inrnthe high thermal flux zones like the plasma divertor. Thernpossibility to use W on the first wall, facing the plasma isrnconsidered as well. The activation properties of thernmaterials used for next generation of fusion facilities arerncarefully studied in order to reduce the radiationrninventory and hazard. Specific "ad hoc" computer codesrnand databases are under development in the fusionrncommunity to predict the radiation issue in ITER. Thernactivation databases for the most important ITERrnstructural materials have been already validated.rnPresently studies of the activation properties of the mostrnimportant material impurities are under way. Rhenium isrnone of the most common impurity elements in Tungsten. Inrnthis paper the activation characteristics of Rhenium havernbeen studied, irradiating some samples with the 14 MeVrnneutrons produced with the Frascati Neutron Generatorrn(FNG) and measuring the induced gamma and betarnactivation. The experimental results have been comparedrnwith the FISPACT code prediction, using the latestrnversion of the European Activation File, EAF-2007. Thernresults of the comparison and the uncertainty analysis arernpresented in the paper.