Physics of runaway electrons with Shattered Pellet Injection at JET

Runaway electrons (RE) are one of the consequences of tokamak plasma disruptions. They may form multi-MA beams of electrons up to several MeV. Avoidance or suppression of such beams is therefore required to ensure reliable operation of future tokamaks. Shattered Pellet Injection (SPI) is the disruption and runaway mitigation method planned for ITER.