The Experiment "pustarex" for Collective Acceleration of Heavy Ions in Electron Rings

The Pustarex experiment is designed to demonstrate the possibility of collective acceleration of highly charged heavy ions in electron rings to a few MeV/amu in an acceleration length of about 1 m. It employs mainly static magnetic fields, such as must be applied in a practical electron ring accelerator. Only for the compression phase and the transport of the ring to the accelerator does the experiment take advantage of fast pulsed fields. Near the end of compression the electron ring can be doped with ions by passing it through a cluster beam. Between compression and acceleration the ring can be held in a static mirror field, the so-called "Wartesaal" (waiting room), where the heavy ions can be ionized by the ring electrons to high charge states. As the accelerating radial component of the magnetic field is limited to a few 10-4 of the guiding axial field the coils had to be built with high accuracy. A few results of pre-experiments and magnetic field measurements are reported. The actual status of the experiment is described including the electron beam system and the vacuum technology.