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Abstract: Gamma radiation-induced optical absorption in 75SiO2–22Na2O–3CaO (wt.%) multi-component glass and in the same glass additionally doped with 0.05wt.% CeO2 has been studied, with irradiations performed at 70, 200, and 350°C, 25kGy/h up to a dose of 0.6MGy. For the undoped glass irradiation at 70°C produces strong optical absorption from 700nm down to the UV. Irradiation at 200°C gives a lower level of optical absorption with a similar band composition. No induced optical absorption has been detected after irradiation at 350°C. Annealing at 200°C for 24h completely suppresses the induced optical absorption. Introduction of cerium increases the level of induced absorption in the UV range for irradiation at 70°C, and also creates bands stable up to 350°C. The results show that silica and sapphire, which are considered as main candidate materials for ITER diagnostic windows and other optical components, can potentially be complemented with multi-component silicate glasses. These materials may allow one to control the radioluminescence, and in addition provide a range of refractive indices required for achromatic lenses. [Copyright &y& Elsevier]

Abstract: Diagnostic components and heating and current drive systems will be used within the vacuum vessel of the future fusion reactors, and especially in ITER. They will have to withstand harsh conditions in terms of neutron and gamma radiations, temperatures, applied voltages and vacuum. In order to study the degradation phenomena of the insulation and window materials and to qualify prototype systems, a representative environment must be available to perform reliable evaluation tests. A multi-purpose irradiation facility has been therefore designed to fit the BR2 experimental fission reactor in Mol, Belgium. This reloadable facility allows a full control of the irradiation conditions (up to 1014ncm−2 s−1 and 500°C) in a vacuum or inert atmosphere, with in-situ bias and measurement capabilities. [Copyright &y& Elsevier]

Abstract: We report on the radiation assessment of hydrogenated aluminium coated 200μm pure silica core fibres. It is experimentally demonstrated that hydrogen protected the fibres against the radiation-induced absorption. With such appropriate hydrogen treatment the fibres can survive the ITER radiation environment in the vicinity of the labyrinth region of the tokamak reactor. [Copyright &y& Elsevier]

Abstract: Radiation hardness assurance for ITER is based on extensive radiation testing. To be representative, these tests must involve an in situ follow-up of the radiation induced changes. SCK·CEN—the Belgian Nuclear Research Center is operating different irradiation facilities with broad possibilities of environmental control and on-line instrumentation. We describe those facilities and outline several recently completed and on-going experiments to illustrate capabilities for testing under conditions relevant for ITER. [Copyright &y& Elsevier]

The future International Thermonuclear Experimental Reactor (ITER) requires remote handling tools for its maintenance that will operate in a harsh environment. The numerous instrumentation cables for this maintenance equipment call for (de)multiplexing solutions, in order to reduce the umbilical size. Fibre-optic data links, using commercial-off-the-shelf (COTS) components, are seriously considered as a radiation tolerant solution, offering wavelength encoded multiplexing possibilities. However, an adapted modus operandi for a reliable assessment of this evolving technology is needed, to enable their long-term implementation in a radiation environment. In this paper, we present a methodology towards qualification methods for these instrumentation data links, and illustrate it with results obtained for different individual components. These results should enable the future design of robust architectures for communication links. [Copyright &y& Elsevier]