ITPA Pedestal and Edge Physics Topical Group

Scope

In order to develop the physics basis for ITER operation, the Pedestal and Edge Physics Topical Group shall coordinate pedestal plasma physics research; initiate collaborative research activities among international fusion research establishments to improve the understanding of pedestal physics, with a focus on the key questions for ITER; develop, maintain and analyze the international pedestal databases, assessing the implications for ITER; and carry out theory and modelling, integrated with experimental activity, to advance scientific knowledge and to reduce uncertainties in predictions for fusion devices such as ITER. Based on these activities, the Topical Group shall make recommendations for the physics research areas and methodologies to address key remaining questions for pedestal fusion research. Since the region treated by the Pedestal and Edge Physics Topical Group is the boundary between the core and the Scrape-Off-Layer (SOL)/divertor regions, and the topic has implications for ITER diagnostics as well as overlaps with magnetohydrodynamics (MHD), the group shall seek to benefit from collaborative activities with the other Topical Groups.

Tasks

The primary tasks of the Pedestal and Edge Physics Topical Group are to:

• Improve our understanding of pedestal and edge physics:
  • The H-mode transition mechanism and edge pedestal structure including the impact of external controls
  • The origin, dynamics and control of edge localized modes (ELMs), including accessibility to the small ELM regimes and their relevance for ITER
  • The interplay between core, SOL and pedestal, including the impact of pedestal phenomena (pedestal structure, ELMs, etc.) on the core and SOL (core confinement, heat and particle flows, etc.)
• Identify self-consistent solutions for the pedestal of ITER:
  • Operating regimes for ITER with pedestal properties compatible with the required core confinement and power and particle exhaust requirements