Cooling of highly charged ions in a Penning trap for HITRAP

The HITRAP (Highly charged Ions Trap) facility is being set up at GSI, Darmstadt. It will enable high-precision atomic physics investigations on heavy, highly charged ions at extremely low energies. Species up to U^92+ as well as radioactive nuclides will be produced at the GSI accelerator complex by stripping of all or nearly all electrons from relativistic ions. Injected into the Experimental Storage Ring (ESR), they will be electron-cooled and decelerated to 4 MeV/u. Bunches of 10^5 ions will be further decelerated in the HITRAP linear decelerator down to 6 keV/u and injected in a Penning trap. In this so-called Cooler Trap they will be cooled to 4 K via electron and resistive cooling before being sent to the experimental set-ups. The physical and technical design of the Cooler Trap has been conceived and optimized for this purpose. Moreover, the cooling processes for a high number of highly charged ions, and in particular the resistive cooling technique, have been systematically investigated in extensive simulations for the first time in order to gain sufficient information both for a general understanding and the design of the Cooler Trap