Investigation of radiation power and carbon evaporation in infrared sensor bolometer

The thin-foil infrared sensor bolometer (IRSB) has been developed on the KSTAR to measure the rapid change of intense radiation during plasma disruption. Despites its successful commissioning, several issues have been identified regarding the interpretation of the measured time scale of the radiation and the durability of the foil. Concerning data interpretation, we propose an extended analysis model with the concept of effective heat capacity for a non-uniformly heated foil, allowing estimation of radiation power during plasma disruption. Concerning device durability, the carbon-coated foils are prone to surface evaporation in high-energy environment. As an alternative, we fabricate buckypaper foils composed of stable multi-walled carbon nanotubes, demonstrating high-temperature stability and superior light absorption.