Lithization of the FTU tokamak with a critical amount of lithium injection

FTU plasma discharges with an extremely high amount of Li injection have been performed using a poloidal liquid lithium limiter acting as the principal Li source in the shadow of the main TZN toroidal limiter. Very peculiar of these discharges is the formation of a 'virtual' toroidal lithium limiter that redistributes the energy flux to the tokamak vessel first wall by radiative processes and therefore decreases the heat load onto the Mo limiter. These experiments contribute to the investigation of a more complex scenario that will possibly be faced by a project of a liquid lithium divertor in a tokamak with high additional power (or high power load on to the targets). (paper)