The Cryogenic Storage Ring and its application to molecular ion recombination physics

The Cryogenic Storage Ring (CSR), presently under construction at the Max-Planck-Institute for Nuclear Physics, will allow the storage of large ionic molecules under optimum experimental conditions. The electrostatic beam optics and the presence of a low-energy electron cooler will allow highly-precise recombination experiments with molecular ions of 160 atomic mass units per charge state. The all-cryogenic design of the storage ring will provide unprecedented vacuum conditions and assure long storage times even for very heavy ion beams. Suppression of the black body radiation background of the beam pipe in combination with electron cooling will give access to internal ion temperatures of 10K and allow state-selective experiments on infrared-active species, impossible in present-day room-temperature storage rings. We give an overview of the CSR project, point out the scientific opportunities arising from its unique design, and give an outlook on possible first molecular recombination experiments after commissioning of the storage ring.