1. Session I-B – Overview Talks Lithium in Magnetic Confinement Experiments S. MirnovLi collection experiments on T-11M and T-10 in framework of Li closed loop concept G. MazzitelliPlasma behavior in presence of a liquid lithium limiter F. TabarésRecycling & Sputtering Studies in H & He Plasmas under Lithiated Walls in TJ-II P. InnocenteLithization on RFX-mod reversed field pinch experiment Summary by M.G. Bell

2. ISLA2 / Summary IB / M. Bell / 110429 2 Li collection experiments on T-11M and T-10 in framework of Li closed loop concept - S. Mirnov In T-10, pre-coating of rail limiter with lithium from a movable probe produced significantly lower Z eff (~1.2), P rad, recycling In T-11M, now using rail limiter with W-felt lithium CPS with water heating/cooling at 200°C –Withstood 1000 shots with 10MW.m -2 for 0.2s Baffles on side of rail limiter assembly (further from LCFS) collected 60±20% of lithium evaporated by plasma from CPS Then added stainless-steel poloidal ring limiter in shadow of CPS –Decreased decay length of lithium distribution in outer region Lithium deposited on side of CPS and ring limiter again ~60% Leads to concept of lithium recirculation system from an inner source through SOL to an outer collector –Periodically reverse source & collector: “Badminton” recirculator –Could remove significant SOL power by non-coronal Li radiation (ITER?)

3. ISLA2 / Summary IB / M. Bell / 110429 3 Plasma behavior in presence of a liquid lithium limiter - G. Mazzitelli 3 heated lithium CPS units - one unit now with W-mesh (others SS) –CPS ~1.5cm outside LCFS for applying Li Lowers P rad, raises density limit (n/n G 1.3–1.5), peaks n e profile (n e (0)/ ≤ 2.5) and lowers n e, increases T e in SOL Improves performance, reproducibility and recovery from disruption –Experimenters now ask for lithium With peaked n e max.  E up 40%,  e reduced by factor 2 –Modeling with gyro-kinetic code and B2-Eirene for edge n e Measured temperature of CPS surfaces and inferred heat loads –In normal case, T max,CPS ~ 450°C after 1s: heat load ~1.5MW.m -2 –By moving LCFS onto CPS, T max,CPS ~ 600°C and saturates –Heat load increases to ~5MW.m -2 and 14MW.m -2 at disruption No damage seen on surface of CPS units –Local lithium radiation limits heat flux to mesh

4. ISLA2 / Summary IB / M. Bell / 110429 4 Recycling & Sputtering Studies in H & He Plasmas under Lithiated Walls in TJ-II - F.L. Tabarés >3 years operating with evaporated lithium (+ boron): ~10000 shots. Produces low recycling for H (10%) and He (82%) at RT –Diffusion limited release of trapped He into subsequent H plasmas Highly improved density control Routine operation with 0.8MW NBI heating Transition to H-mode: confinement doubled, turbulence decreased –ELMs appear and fluctuations transiently increase Development of peaked profiles: “bell”  “dome” at high n e Li sputtering a factor 10 below expectation after GDC: Li bonding? –Investigating properties of Li surface in test stand; in situ in future Plan to install Liquid Lithium Limiter in 2011 (Red Star collaboration) –Including possibility of biasing –Test possibility of fuel recovery from lithiated system

5. ISLA2 / Summary IB / M. Bell / 110429 5 Lithization on RFX-mod reversed field pinch experiment - P. Innocente Graphite PFCs provide almost infinite reservoir of H –Bakeout, HGDC, HeGDC, boronization to control impurites, reduce H Li pellet injection into plasmas with bare & boronized PFCs – 5mg each, 50–200m/s  1g total Controls density, increases n e (0)/, reduces C & O –Effect decays after a few shots: lithium removal or reaction with H? Now using liquid lithium CPS as evaporator and limiter (ablation) –Helical deformations can lead to strong interaction  damaged surface –Tokamak-like discharges could be used to distribute Li toroidally –Also observed carbon buildup on unit –Effects on plasma similar to pellets Lithium penetrated >50nm into graphite PFCs (SIMS) Limited access prevented cleaning Li residue from PFCs after vent –Needed H-,He- GDC and plasma discharges to re-establish clean plasmas Considering installing 4 Li evaporators and centrifugal pellet injector