Production and acceleration of tracer encapsulated solid pellets for particle transport diagnostics

A new method for producing a tracer-encapsulated solid pellet (TESPEL) has been developed for a local deposition of the tracer ions in the core plasma and an accurate measurement of the particle transport. The method allows manufacturing of TESPELs in the form of polystyrene shells containing lithium hydride inside as a tracer. The TESPEL acceleration has been successfully performed and photos of the pellets in flight confirmed the TESPEL integrity. For the pellets with diameter 300–400 μm and wall thickness 40–50 μm the pellet fragility becomes insignificant. Calculation of the TESPEL ablation rate has showed that the achieved pellet velocities and sizes are appropriate for the injection into a medium size plasma. It was proposed to fractionate the tracer contents in order to provide better localization of the deposited tracer ions in the plasma. The data obtained in these experiments have proved that injection of the TESPEL made from the plastic shells can be a promising tool for the particle transport diagnostics.