Impact of Low- and High-Z Ion-induced Damage on the Reflectivity of Molybdenum Mirrors and Sub-surface Microstructure

Ł. Ciupiński (Warsaw Univ. of Techn., Poland)

Transmission of optical signals from plasma in controlled fusion devices is the fundament of plasma diagnosis using optical spectroscopy and imaging techniques. They serve both physics studies and machine control and protection. Therefore, quality of optical components, such as mirrors and windows, is essential to ensure both reliable plasma operation and high-level research. In a reactor-class machine operated with a deuterium-tritium fuel, the lifetime of windows would be strongly reduced under gamma and neutron irradiation. This work is focused on the determination of: (i) mirror performance following multiple ion irradiations with heavy and light species, (ii) structural changes in the optically active layer of the irradiated mirrors, (iii) the threshold dose for optical degradation.