New techniques at ISOLDE-2

Experiments at the reconstructed on-line isotope separator facility ISOLDE-2 at the CERN 600 MeV synchrocyclotron are now in progress. Over the past year the extracted proton beam has been raised to 1.3 mu A, and the design value of 5 mu A is now within reach. The target and ion-source technology developed before the reconstruction has been further improved so as to permit the utilisation of the high proton- beam intensities and to increase the range of elements available for study to 30. With a proton-beam intensity of 0.7 mu A the radioactive Cs/sup +/ beams after mass separation have increased by a factor of 300 and, in the most favoured cases, are exceeding 6 nA. This permits the visualisation of the separated radioactive ion beams by means of the usual beam scanners. A new target concept, a finely divided metal powder at ultra-high temperatures, features a short delay component which enhances the yield of very short-lived products. The new beam- optical system supplies four measuring stations simultaneously and allows up to ten groups to take data during an ISOLDE run (typically 100 h). (13 refs)