50 years GSI



The new accelerator facility FAIR is under construction at GSI. Learn more.


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GSI ring accelerator in operation again

More than one year of construction works for the future accelerator facility FAIR



After one year of construction works the large ring accelerator with a circumference of 216 metres of the GSI Helmholtz Centre for Heavy Ion Research in Darmstadt is in operation again. Today the first scientific experiment has started. The researchers examine the influence of cosmic radiation on manned space flight. With the construction works at the ring, the so called heavy ion synchroton SIS, first technical requirements have been met to enable the ring to serve as the designated pre-accelerator for the future FAIR accelerator facility. FAIR is currently being built in an international effort and will be connected to the GSI accelerators.

In the experiment started today the scientists investigate the influence of cosmic radiation on cells and the shielding properties of various materials in cooperation with the European Space Agency, ESA. The findings are crucial for manned space flight, as astronauts are permanently exposed to cosmic radiation during space travel. With the GSI accelerator facility ion beams can be generated as they occur in space. This enables scientists to analyse their effects in the laboratory and develop precautions for space flights.

It is planned to keep the ring accelerator continuously running for 24 hours per day until the midmonth of May. Scientists from other fields, like nuclear physics, atomic physics, materials research and biophysics, will use the time for various other experiments.

The vital novelty of the construction works was the integration of a new accelerator cavity. The SIS ring now consists of three instead of two cavities. In the coming years additional construction works will take place, among them the mounting of two more cavities. With the total of five accelerator cavities the SIS will have the capacities to accelerate all kinds of elements and inject them into the FAIR facility.


New SIS cavity
Irradiation of cells
The new accelerator cavity (square silver setup in the front) is necessary for the future operation with FAIR. In the background deflecting magnets (red) and focussing magnets (yellow).
In the current biophysics experiments the scientists investigate the influence of cosmic radiation on cells.
Foto: G. Otto, GSI Helmholtzzentrum für Schwerionenforschung
Foto: G. Otto, GSI Helmholtzzentrum für Schwerionenforschung