STATUS OF THE LASER ION-SOURCE AT THE LEUVEN ISOTOPE SEPARATOR ONLINE

An online laser ion source has been used at the Leuven isotope separat or online for the production of pure beams of exotic nuclei. The opera tional principle of the ion source is based on the element-selective m ultistep laser resonance ionization of nuclear reaction products therm alized and neutralized in a high-pressure noble gas. A number of impro vements has been carried out to obtain stable and reproducible operati on. The ion source has been optimized for the production of beams of e xotic nuclei, created in proton-induced fission reactions. The efficie ncy of the ion source has been improved by incorporating the sextupole ion guide to separate laser-produced ions from the gas jet and to tra nsport them to the acceleration stage of the mass separator. A gas pur ification system has been installed to purify the noble gas down to pp b level. High selectivity and efficiency of the ion source allowed to collect nuclear spectroscopic information for the neutron deficient Ni -54 and neutron-rich Ni68-74 isotopes. (C) 1998 American Institute of Physics.