MHD Activity in FTU Discharges With a Liquid Lithium Limiter

Experiments on plasma configurations with Liquid Lithium Limiter (LLL) have been performed on FTU to investigate liquid lithium facing the plasma. The liquid lithium surface with capillary porous system (CPS) has been inserted in the scrape off layer (SOL) of the FTU vacuum chamber in various plasma discharges. MHD activity in discharges with and without LLL has been investigated and compared. The main MHD effect observed with LLL is a reduction of the amplitude of tearing modes with poloidal (toroidal) number m = 2 (n = l). The magnetic activities in FTU are analysed by means of a set of poloidal field pick‐up coils. A total of 57 coils are installed at various toroidal and poloidal positions. In this paper we will describe in details the diagnostic apparatus and experimental results.