Since the publication of Progress in the ITER Physics Basis in 2007, extensive studies have addressed major challenges in tokamak fusion plasma physics, with the International Tokamak Physics Activity (ITPA) playing an instrumental role in coordinating experimental, theoretical, and computational efforts. These findings are compiled into a special issue “on the path to tokamak burning plasma operation” in Nuclear Fusion.
The special issue aims at providing a comprehensive review of progress made over the past 18 years across the major areas of tokamak plasma research. Chapters of the issue are now coming on line, starting with Transport and confinement physics and Scrape-off layer and divertor physics. The largest share of the authors are from EUROfusion (and formerly EFDA), which has contributed through the work packages Tokamak Exploitation (WP TE) and Plasma Wall Interaction and Exhaust (WP PWIE) of the Plasma Science for ITER, DEMO and stellarators Department.
Hence progress in physics understanding and theoretical model development of plasma transport and confinement in the ITPA Transport and Confinement (TC) Topical Group are summarized focusing on the contributions to ITER and burning plasma prediction and control. This Chapter provides a general and streamlined overview in the areas of particle transport, impurity transport, ion and electron thermal turbulent transport, momentum transport, impact of 3D magnetic fields on transport, confinement mode transitions, global confinement, and reduced transport modeling.
Significant progress has been made in understanding the processes that determine the properties of the plasma edge region, their influence on the power and particle exhaust, and the interaction of the plasma with the First Wall components. Much of this progress has been achieved through the coordinated research activities of the ITPA Topical Group on Scrape-Off Layer (SOL) and Divertor Physics (DivSOL), in collaboration with the ITER Organisation, and covers a wide range of issues related to stationary and transient power exhaust, erosion of Plasma Facing Components and impurity migration, hydrogen isotope recycling and their storage in the first wall, properties of plasma-facing materials and their evolution under plasma exposure.
More Chapters are expected to come online in a near future, summarizing the research work coordinated by the other Topical Groups of the ITPA on Diagnostics, Energetic Particle Physics, Integrated Operation Scenario, MHD, Disruptions and Control or Pedestal & Edge Physics.
