PRESENT STATUS OF THE 2.45 GHZ ECRIS FOR A LIGHT-ION ACCELERATOR AT IAP

This article presents a 2.45 GHz electron cyclotron resonance ion sour ce which is under construction at the Institute of Atomic Physics Buch arest, Romania. It will be used as an injector into an existing linac for light ions and is a compact version of a similar source, for which we have obtained the magnetic system by superimposing an axial magnet ic field generated by two solenoids and a radial magnetic field genera ted by a permanent magnet hexapole. For the compact version we have em ployed two rings made of permanent magnets for the axial magnetic fiel d and the same type of hexapole for the radial field. This second vers ion will work on a high voltage platform. The calculation, design, and construction of the two minimum magnetic field structures (B minimum) are presented. These sources have a special microwave antenna, of a h elix type, allowing a much smaller diameter plasma chamber than is usu ally used for the employed microwaves. The microwave system is also pr esented. The first experiments were made with an Ar plasma. (C) 1996 A merican Institute of Physics.