The modifications of the JYFL 6.4 GHz ECR ion source

A new JYFL 14 GHz ECRIS was completed in spring 2000 for the nuclear physics program at the Department of Physics, University of Jyvaskyla (JYFL). The old JYFL 6.4 GHz ECRIS (built in 1990-1991) is now also available for the material physics experiments and for the research and development work of the ECR ion sources. During the last year remarkable modifications to the structure of the source have been undertaken. In the first phase, which was completed in fall 2001, the axial magnetic field was optimized using the old power supplies and the coils. The radial magnetic field was improved in spring 2002 by installing an iron cylinder around the hexapole permanent magnets. According to the measurements the improvement of about 25% to the radial magnetic field was achieved. The research work to improve the ion beam quality has been started.