Ultra compact 10 GHz electron-cyclotron-resonance ion source (ECRIS) for the production of multiply charged ions

摘要

There is a growing interest in the use of beams of multiply charged ions produced in special environments like high voltage platforms, Dynamitrons, Van-de-Graaff accelerators or on-line production systems for radioactive beam facilities. A compact 10 GHz ECR ion source (200 mm long, 170 mm diameter) has been developed and tested. The complete magnetic structure made from permanent magnet material is comprised of four ring magnets producing an asymmetric axial magnetic field with a mirror ratio of 2.5 and a 24 piece hexapole magnet with a maximum radial field of 0.94 T inside the plasma chamber of 25 mm inner diameter. The coupling of the microwave to the plasma using a resonant transition line from rectangular to circular waveguide shows efficient ECR plasma heating at microwave power levels around 10 watts. Charge state distributions for various elements with intensities up to 320 e(mu)A and their dependence on operation parameters will be presented as well as VUV spectra in the wavelength region down to 15 nm.