The ISOLDE facility

The CERN on-line isotope separator facility ISOLDE is a unique tool for stu dying problems in nuclear, atomic, surface and solid state physics, nuclear medicine and astrophysics. Protons in very short high intensity pulses fro m the PS Booster are directed on either one of the targets of the two on-li ne mass separators. The 60 keV ions from them are fed into a common beam tr ansport system to which most of the experiments are connected. The layout o f the facility is presented and a detailed description of the two mass sepa rators and the beam distribution system is given. Also the problems of radi ation shielding and of the handling of radioactivity are discussed.