Faraday cups and scintillation detectors
Alpha particles, produced in fusion reactions, will provide the main heating power in future fusion reactors – the power needed to sustain extreme temperatures of the plasma. Therefore, studies of transport and confinement of fast alpha particles are of prime importance. Due to its size and capabilities, JET confines fast alpha particles produced in two ways: either in actual Deuterium-Tritium fusion, or by injection of Helium beams into the plasma and consecutive acceleration of Helium ions by suitable radio frequency power. The Farady cups and scintillation detectors are dedicated to the direct measurement of lost fast alpha particles. They are capable of monitoring lost alpha particles by measuring their fluxes, crude spatial distributions and velocity components. Faraday cups estimate the integral particle fluxes, the scintillation detectors do the same by sampling individual particles.