The interaction of radio-frequency fields with fusion plasmas: the JET experience

The JET Task Force Heating is proud to present this special issue. It is the result of hardand dedicated work by everybody participating in the Task Force over the last four years andgives an overview of the experimental and theoretical results obtained in the period 2008–2010with radio frequency heating of JET fusion plasmas. Topics studied and reported in this issueare: investigations into the operation of lower hybrid heating accompanied by new modelingresults; new experimental results and insights into the physics of various ion cyclotron rangeof frequencies (ICRF) heating scenarios; progress in studies of intrinsic and ion cyclotronwave-induced plasma rotation and flows; a summary of the developments over the last yearsin designing an ion cyclotron radiofrequency heating (ICRH) system that can cope with thepresence of fast load variations in the edge, as e.g. caused by pellets or edge localized modes(ELMs) during H-Mode operation; an overview of the results obtained with the ITER-likeantenna operating in H-Mode with a packed array of straps and power densities close to thoseof the projected ITER ICRH antenna; and, finally, a summary of the results obtained in applyingion cyclotron waves for wall conditioning of the tokamak.This issue would not have been possible without the strong motivation and efforts(sometimes truly heroic) of all colleagues of the JET Task Force Heating. A sincere wordof thanks, therefore, to all authors and co-authors involved in the experiments, analysis andcompilation of the papers. It was a special privilege to work with all of them during the pastvery intense years.Thanks also to all other European and non-European scientists who contributed to the JETscientific programme, the operations team of JET and the colleagues of the Close Support Unitin Culham. Thanks also to the editors, Editorial Board and referees of Plasma Physics andControlled Fusion, together with the publishing staff of IOPP, who have not only supportedbut also contributed very substantially to this initiative. Without their dedication this issuewould not have been possible in its present form.A special word of thanks to Marie-Line Mayoral and Joelle Mailloux for their precioushelp and very active support in running the JET Task Force Heating over the last years. WithoutJoelle and Marie-Line itwould have been a much more daunting task to prepare JET operations,monitor progress during the experiments and edit the papers that are compiled here.