Beam Development/Implementation and Futher Development of the ISOLDE Laser Ion Source

% IS335 \\ \\ Already before the move to the PS-Booster (PSB) the proton-beam time-structure of 7 pulses of 2.4~$\mu$s duration every 1.2~s was identified as the major challenge to the target and ion-source technique. It was also recognized that an intensive target development programme should be undertaken in order to exploit efficiently the properties of the Booster beam. This beam structure can have both beneficial effects and deleterious effects on the performance of the targets. On the one side the power deposition, the shock wave and the cascade of nuclear reactions may enhance the release and make the targets faster. \\ \\The selectivity with which ISOLDE can separate the products according to the chemical element is another important parameter for the experiments. Online test experiments at the SC ISOLDE-3 successfully demonstrated that resonant multi-photon excitation and final ionization by pulsed lasers is an efficient tool for the production of isobarically pure ion beams. The installation of a permanent laser ion-source at the PS-BOOSTER ISOLDE facility is proposed. Combined with existing target technology this will open up a new efficient way to produce isotopically pure ion beams from a number of targets where the conventional ion source technology failed with respect to chemical selectivity. The obtained gain in sensitivity of a factor of 10$^{4}$ together with the bunched beam structure open up new perspectives for spectroscopy on nuclei far from stability, in the mass measurement programme, in materials research and in laser spectroscopy.