This special issue highlights the continued progress and new insights gained with the JET facility, which is now being operated under EFDA (European Fusion Development Agreement), a structure in which all European Associations participate actively and work together for a common goal. The current set of papers intends to give a broad overview of the work completed in the period 2000-2001 in the framework of the so-called Task Force Scenario 1. This Task Force has the mission of studying the physics of the ELMy H-Mode, the reference scenario for ITER. Plasmas with improved performance at high density have been demonstrated making use of strong shaping, impurity seeding and pellet injection. The results constitute an important extension of the H-mode database at high density and high energy confinement. Special attention is given to the characterization and mitigation of Edge Localized Modes (ELMs) which can present a large instantaneous heat flux to the divertor. Various other aspects of H-mode plasmas are addressed, in particular the physics and implications of spontaneous peaking of the density profiles and the characterization of the H-mode pedestal for the new configurations explored. In finalizing this cluster of articles, thanks are due to all colleagues involved in preparing and executing the JET programme under EFDA: the participants in the programme of the Task Force S1 and all other European and non-European scientists who contributed to the JET scientific programme, the Operating Team of the JET facility and the colleagues of the Close Support Unit (CSU). Thanks are also due to the Editors, Editorial Board and Referees of Plasma Physics and Controlled Fusion together with the Publishing Staff of IOPP who have supported and contributed substantially to this initiative.
Fusion physics progress on JET
H-mode plasmas in the pre-fusion power operation 1 phase of the ITER research plan