The CRYRING accelerator facility

In the last months of 2012 and the first months of 2013 CRYRING was moved to Darmstadt in Germany, as described on the History page. The information on this page has been kept for historical reasons, and reflects the situation in 2010.

The CRYRING facility at the Manne Siegbahn Laboratory consists of a small ion synchrotron and storage ring with electron cooling, an RFQ linear accelerator and two injectors for different types of ions.

The operation of the CRYRING facility for physics experiments was ended in December 2009. After some concluding tests related to the planned transfer of the ring to FAIR in Darmstadt it was then taken out of use in the spring of 2010. The ring will now be modified, dismounted and packed in boxes for transport to Germany.

The ECR (Electron Cyclotron Resonance) ion source delivers ions of medium-high charge states from a 300 kV platform. It was put in operation in October 2001 for low-energy experiments. The first experiment with ECR ions in the ring, with the platform on high voltage, was in June 2003.

On the MINIS platform, a number of different ion sources can be installed for injection into the RFQ and the ring. It runs on potentials between 10 and 40 kV. So far we have used Nielsen hot-cathode sources with gas injection or an oven, a cold-cathode source for vibrationally cold molecules or reactive substances, a sputtering source for negative ions, a Nier electron-impact source for molecules in known vibrational states and a molecular-beam discharge source for rotationally cold molecules.

An RFQ (Radio Frequency Quadrupole) is used as an intermediate accelerator between the ion sources and the ring. It accelerates ions with charge-to-mass ratios greater than 0.25 from a fixed input velocity corresponding to 10 keV/u to a fixed output velocity corresponding to 300 keV/u. Ions with lower charge-to-mass ratios can be transported through the RFQ without being accelerated, so that they are injected into the ring at the energy given by the voltage of the ion-source platform.

The ring has a circumference of 51.6 m and a maximum rigidity of 1.44 Tm, giving a maximum energy of 96 (q/A)² MeV/u. It has an electrostatic 10-turn multiturn injection, acceleration with a driven drift tube instead of a resonant cavity, and is equipped with electron cooling. The electron cooler, which also acts as an electron target for recombination experiments, uses an adiabatically expanded electron beam which gives electron temperatures down to 10-30 K.