1. Discussions and Summary for Session 1 ‘Transport and Confinement in Burning Plasmas’ Yukitoshi MIURA JAERI Naka IEA Large Tokamak Workshop (W60) Burning Plasma Physics and Simulation Tarragona, Spain July 4-5, 2005 We are asked where are we?, where do we want to go?, how do we get there?

2. Burning Plasmas Scientific importance and interest –Plasma confinement and stability at large scale (small  *) –High energy  particles effects on MHD, equilibrium and confinement –Strong coupling between pressure and heating (self-heating) –Plasma boundary and material interaction –Control and mitigation of disruption, NTM, RWM, STO, ELM, and …. Technological importance and interest –Integration of present technologies –Tritium processing and inventory –High heat flux –Remote handling –Blanket technology –Diagnostic and Control of self-organized plasma

3. D-T Experiment D-T experiments were performed in JET and TFTR

4. Alpha heating without MHD  particles are well confined Classical slowing down of  Electrons are heated by  particles

5. Plasma confinement and stability at large scale (small  *) Beta degradation of ITER confinement scaling Isotope effect on confinement varied depending on operating regime Pedestal structures … At the large scale plasma –Does the confinement change? Will turbulent transport studies both experimental and theoretical help? –Does the stability change?

6. High energy  particles effects on MHD, equilibrium and confinement High energy  particles destabilize some instabilities and stabilize another instabilities. TAE, STO modifies the  distribution. Is it a severe loss or redistribution of  particles? No-linear analysis and comprehensive measurements are necessary for the further understandings How the effects on equilibrium?

7. Strong coupling between pressure and heating (self-heating) There are some limitation of present burning plasma simulation experiments. It will help our understandings. Is it possible to control AT plasmas Other experiment? More comprehensive predictive simulation codes will be necessary. Strategy for the developments? –Transport, High energy, MHD, Stability, Divertor and SOL

8. Plasma boundary and material interaction High heat flux by ELMs -> ELM mitigation Tritium retention in graphite. The method of tritium removal? High Z material? Wall conditioning?, Wall saturation (controlled by divertor pumping)?

9. Control and mitigation of disruption, NTM, RWM, STO, ELM, and …. Disruption -> damage to the machine. Is it possible to know the operational margin by a real time calculation? NTM control j BS ). RWM control <- external coil system will work. Does plasma rotation control necessary? STO -> affect a distribution, impurity accumulation ELM control by shape, rotation, external coils, pellets and etc. JT-60U Example