MPI-K, Heidelberg
Weizmann Institute of Science, Rehovot
TU Dresden, Dresden
UCL, Louvain-la-Neuve
A novel next generation electrostatic Cryogenic Storage Ring (CSR) for heavy ions, molecules and clusters up to bio-molecules in the energy range of 20-300 keV is under construction at MPI Heidelberg. A unique feature of this ring is the possibility to operate it at all temperatures between room temperature down to 2 K. Operation at cryogenic temperatures is inevitably necessary to investigate the properties and reaction modes of molecular ions in their ground state as ,e.g., in interstellar environment. Therefore only cold wall surfaces have to be used to eliminate black body radiation exciting molecular quantum states. In addition, surfaces of 2-10 K will act as a large cryo-pump, expected to achieve a vacuum of better than 10-15 mbar (corresponding to 10-13 mbar at room temperature), which is mandatory for sufficiently large storage times for slow heavy ions. Considerable progress towards realization of this technologically ambitious project can be reported. The detailed layout of the storage ring CSR has been defined. A 2 K-21 W helium refrigerator system was designed, ordered and successfully commissioned at MPI, where it is now in operation to cool the prototype cryostat with its cryogenic ion trap CTF to 2 K temperature.
