2nd Iter International Summer School

This book contains the lectures of the 2nd ITER International Summer School (2008), which was held in conjunction with the 47th Summer School of JSPF for Young Plasma Scientists at Kyushu University during July 22-25, 2008. The theme of the school, “Confinement (from device to plasma)”, was to provide a comprehensive knowledge for fusion research in the ITER era. Fusion research will enter a new phase with ITER, characterized by plasmas with substantial fusion reaction rates, run by an international collaboration effort. Recognizing this new challenge, this book uniquely addresses the definition of mission, the design of device and the knowledge bases for its completion in a consistent manner. This book aims to prepare young researchers to tackle the current and anticipated challenges of magnetic fusion devices, and to disseminate the global knowledge required for a timely and competent exploitation of the ITER physics potential.

This book focuses on tritium as a fuel for fusion reactors and a next-generation energy source. Following an introduction of tritium as a hydrogen radioisotope, important issues involved in establishing safe and economical tritium fuel cycles including breeding for a fusion reactor are summarized; these include the handling of large amounts of tritium: confinement, leakage, contamination, permeation, regulation and tritium accountancy, and impacts on surrounding areas. Targeting and encouraging the students and technicians who will design and operate fusion reactors in the near future, this book offers a valuable resource on tritium science and technology.

This book is a primer on the interplay between plasma and materials in a fusion reactor, so-called plasma–materials interactions (PMIs), highlighting materials and their influence on plasma through PMI. It aims to demonstrate that a plasma-facing surface (PFS) responds actively to fusion plasma and that the clarifying nature of PFS is indispensable to understanding the influence of PFS on plasma. It describes the modern insight into PMI, namely, relevant feedback to plasma performance from plasma-facing material (PFM) on changes in a material surface by plasma power load by radiation and particles, contrary to a conventional view that unilateral influence from plasma on PFM is dominant in PMI. There are many books and reviews on PMI in the context of plasma physics, that is, how plasma or plasma confinement works in PMI. By contrast, this book features a materials aspect in PMI focusing on changes caused by heat and particle load from plasma: how PFMs are changed by plasma exposure and then, accordingly, how the changed PFM interacts with plasma.

The promise of a vast and clean source of thermal power drove physics research for over fifty years and has finally come to collimation with the international consortium led by the European Union and Japan, with an agreement from seven countries to build a definitive test of fusion power in ITER. It happened because scientists since the Manhattan project have envisioned controlled nuclear fusion in obtaining energy with no carbon dioxide emissions and no toxic nuclear waste products.This large toroidal magnetic confinement ITER machine is described from confinement process to advanced physics of plasma-wall interactions, where pulses erupt from core plasma blistering the machine walls. Emissions from the walls reduce the core temperature which must remain ten times hotter than the 15 million degree core solar temperature to maintain ITER fusion power. The huge temperature gradient from core to wall that drives intense plasma turbulence is described in detail.Also explained are the methods designed to limit the growth of small magnetic islands, the growth of edge localized plasma plumes and the solid state physics limits of the stainless steel walls of the confinement vessel from the burning plasma. Designs of the wall coatings and the special 'exhaust pipe' for spent hot plasma are provided in two chapters. And the issues associated with high-energy neutrons — about 10 times higher than in fission reactions — and how they are managed in ITER, are detailed.

This school aims at preparing young researchers to tackle the current and anticipated challenges at magnetic fusion devices, and spreading the global knowledge required for a timely and competent exploitation of the ITER physics potential. The 5th edition is an overview of MHD interacting with energetic particles issues, with regard to ITER project.

The lectures given in the Summer School covered most of the important topics in controlled nuclear fusion and high temperature plasma physics. The topics are as follows: tokamak research, stellarator physics, transport and confinement of high temperature plasma, plasma-wall interaction and edge plasma physics, heating and current drive, diagnostics and general plasma theory.