Plasma surface interactions under burning plasma state in a fusion reactor

Important issues are pointed out and briefly discussed on plasma surface interactions under burning plasma state and the plasma facing components. For the success of self-ignition for a long time period, it is necessary to control the heat and particle flow to plasma facing components and their interactions. For the heat removal, reliable high heat flux components have to be developed. The lifetime of plasma facing components also has to be lengthened. The development of tritium fuel cycle and the reduction of tritium in-vessel inventory are now strongly required. Since the plasma facing materials are damaged both by fusion neutron and energetic helium, such the studies have to be progressed. For the sustain of the burning plasma state, effective helium pumping such by the use of helium pumping material is desired. For a fusion reactor, the developments of low activation materials and high Z materials are required. In the present report, the progresses of above the issues are described and the further problems are addressed. (author)