Recent lithium experiments in tokamak T-11M

The T-11M lithium program is focused to find solutions for technological issues of a steady-state tokamak. A recent lithium activity in T-11M was focused on three directions: investigation of different Li-limiters, investigations of long-term effects of lithium behavior in hydrogen plasmas and development of a new kind of CPS limiters. The new so-called R limiter has been used as Li collector for investigation of lithium fluxes near the plasma boundary and chamber walls. It was shown, that the Li circulation near the limiter exceeds up to four times the primary lithium flux from limiters. 90% of primary flux is collected by lateral sides of limiter and only 10% arrives at the chamber wall. The deuterium glow discharge was used to test the long-term lithium degradation under the deuterium bombardment. It was shown that such degradation is small. That means that the Li-limiter can be used as Li-emitter in steady-state tokamak operation. A new vertical lithium limiter was successfully tested in T-11M.