Electron Cyclotron Resonance Ion Sources produce ion beams of Multiply Charged Ions for accelerators. Our goal is to develop the new technologies needed for a significant step towards higher currents and higher charge states. Improvements will result from:
(i) higher frequencies: 25 GHz gyrotron;
(ii) specially-designed extraction systems adapted to high currents;
(iii) higher magnetic fields: super conducting magnets.
This projects is divided in two main parts:
1.Design: (1.1) 28 GHz line and injection systems (1.2) high current extraction systems; (1.3) superconducting devices, and related technologies;
2. Experiments: (2.1) coupling of a 28 GHz wave into a large source; (2.2) construction of the Phoenix source and test at 28 GHz; (2.3) new developments for pulsed discharges; and (2.4) test of an autonomous cryocooler.
Alain Girard, Département de Recherche Fondamentale sur la Matière Condensée-Service des Ions, Atomes et Agrégats, 17 rue des Martyrs, Grenoble 38054, France
During the three years of this project, a high frequency (28 GHz) high power microwave transmitter was coupled to a high flexibility superconducting source (SERSE at INFN-LNS); important scaling laws were both confirmed and derived there. Then the gyrotron was moved to ISN and coupled to the Phoenix source, especially designed for this project, for afterglow and High Voltage operation. In both sources the results were outstanding and beam intensities never obtained before were measured. In the Phoenix source lead ions were produced and reached intensities still never obtained. In this field new processes for metallic ion production have been developed, especially at GSI, and a high temperature oven built. The problem of ion extraction in the new sources is fundamental: as high currents are extracted, it is necessary to optimise the design of the extraction system.
For that purpose the codes should be able to accurately model the plasma-beam interface; therefore the existing code for ion extraction at GSI has been modified to take into account more accurately the physics of ion extraction, both from the geometrical point of view (3D effects due to the shape of the plasma), and from the plasma point of view (hot electrons are considered). This code has been used for the calculation of the ion extraction from GyroSerse. The study of the Gyroserse source - a high confinement superconducting source optimised for 28 GHz operation - is part of this project: its main characteristics have been chosen, after the tests in the SERSE source, and an advanced conceptual design of the source has been performed; the development of a cryocooler has been achieved, and a conceptual design of the A-Phoenix source has been done.
Funding SchemeCSC - Cost-sharing contracts