THE CRYOGENIC STORAGE RING PROJECT AT HEIDELBERG

At the Max-Planck-Institut für Kernphysik (MPIK) in Heidelberg a next generation electrostatic storage ring at cryogenic temperatures is under development. The main perspective of this unique Cryogenic Storage Ring (CSR) is the research on ions, molecules and clusters up to biomolecules in the energy range of 20-300 keV at low temperatures down to 2 K. The achievement of such temperatures for all wall materials seen by the ions in the storage ring not only causes a strong reduction of black body radiation incident onto the stored particles, but also acts as a large cryopump, expected to achieve a vacuum of better than 10-15 mbar (corresponding to 10-13 mbar at room temperature). The low temperature and the extremely high vacuum (XHV) will allow novel experiments to be performed, such as rotational and vibrational state control of molecular ions during their interaction with ultra-low energy electrons and laser radiation. A 2 K/21 W refrigerator was successfully commissioned. The connection with a fully assembled cryogenic prototype ion trap is finished and results of first cooling tests will be presented. In this paper we describe the concept and the status of the CSR