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


GSI is member of


Funded by




17.12.2009 | 40 Years GSI - 40 Years of Leading International Research

Foundation of GSI on December 17, 1969

G. Otto/GSI Helmholtzzentrum für Schwerionenforschung GmbH

Linear accelerator

A. Zschau/GSI Helmholtzzentrum für Schwerionenforschung GmbH

Ring accelerator


40 years ago, on December 17, 1969, the GSI Helmholtzzentrum für Schwerionenforschung was founded in Darmstadt then still under the name Gesellschaft für Schwerionenforschung.

GSI is a research center financed by the German federation and the federal state of Hesse with a yearly budget of over 100 million euros. GSI runs a large, worldwide unique accelerator facility for ion beams, i.e. beams of charged atoms. Annually more than 1,200 scientists from all over the world use the ion beams for their experiments in fundmental research. The research program comprises a broad spectrum, ranging from nuclear and atomic physics to plasma and materials research right up to biophysics and medicine. GSI’s most prominent advancements are the discovery of new chemical elements, such as element 110, Darmstadtium, and the development of a novel cancer therapy using ion beams, which just recently went into routine operation in hospitals. Other examples of outstanding research are the discovery of hundreds of new isotopes and the detection of new types of radioactive decay. GSI will also be the location the new international accelerator facility FAIR (Facility for Antiproton and Ion Research), a 1.2 billion project that will be realized in the near future.

Discovering New Elements

Scientists at the GSI Helmholtzzentrum accelerator facility discovered six new chemical elements, which carry the atomic numbers 107 to 112. After their new elements were officially approved by the International Union of Pure and Applied Chemistry IUPAC, the discovering teams had the honor to suggest a name for their element. GSI already named five of the six elements: element 107 is called Bohrium, element 108 Hassium, element 109 Meitnerium, element 110 Darmstadtium, and element 111 is named Roentgenium. A few months ago, IUPAC officially recognized the new element 112 and GSI proposed to name it Copernicium. As is customary, the suggested name will be evaluated by the scientific community during the next six months. Besides discovering new elements, GSI researchers explore the universal question of how the chemical elements, which are the building blocks of our life, came into existence. GSI scientists try to replicate the conditions that prevail inside stars, because, just like the matter that surrounds us, the atoms that make up our bodies stem from stardust created in earlier generations of stars.

Ion beam cancer therapy

Together with medical experts, GSI scientists developed and successfully implemented a world novel ion beam cancer therapy at GSI’s accelerator facility. Ion beam cancer treatment is precise, highly effective and very gentle for the patient. On the GSI therapy place 440 patients were treated, they experienced very little side effects and showed a cure rate of over 90 percent. A few weeks ago, the first public ion beam cancer treatment facility “Heidelberg Ion Beam Therapy Centre” (HIT) took up routine operation. Its accelerator and irradiation technology were developed by GSI scientists and engineers. In the scope of a license agreement between the GSI Helmholtzzentrum and Siemens AG, two more facilities modeled on HIT are under construction in Marburg and Kiel, Germany.

Foundation and Development of GSI and its Research Facilities

The formation of the Gesellschaft für Schwerionenforschung was initiated by professors from the Universities of Heidelberg, Marburg, Darmstadt, Frankfurt, Mainz and Gießen. Together, they developed a new heavy ion accelerator and measuring technology for their experiments at this new facility. Building such a facility was beyond the means of an individual university. With GSI, a laboratory with large-scale equipment for the research on heavy ions was now open to all universities. On December 17, 1969, the federal state of Hesse and the German federation signed the GSI’s partnership agreement, with the state of Hesse bearing 10 per cent and the German federation bearing 90 per cent of the costs. In 1975, the first accelerator, the 120 meter long Universal Linear Accelerator UNILAC was commissioned. UNILAC can accelerate ions of all chemical elements to a fifth of the speed of light. In April 1976, ions of the heaviest natural element, Uranium, were accelerated for the first time and when the ions hit their target, GSI scientists were able to observe nuclear reactions.

In April 1990, a second accelerator was commissioned. This new circular accelerator, a so-called synchrotron, has a circumference of 216 meters and features a storage ring with a circumference of 108 meters. It is able to accelerate the ions to a velocity of up to 90 per cent of the speed of light. Now, GSI has started preparations for its new international accelerator facility FAIR (Facility for Antiproton and Ion Research), one of the world’s largest projects for fundamental research in the field of physics. FAIR will comprise eight circular accelerators of up to 110 meters circumference, two linear accelerators and some 3.5 kilometers of beam guide tubes. GSI’s existing accelerators will be used as pre-accelerators for FAIR. The new FAIR facility will provide antiproton and ion beams of hitherto unreachable intensity and quality. The facility has an investment volume of 1.2 billion euro and will be realized in international cooperation.


Through the initiative of GSI the heavy ion program has been established at CERN. For this GSI built a heavy ion injector and participated in several major experiments since the 1980s. From the start GSI together with the universities of Darmstadt, Frankfurt, Heidelberg and Münster was and will be involved in the construction and the scientific program of ALICE (A Large Ion Collider Experiment) in a leading role. Furthermore the World Wide Grid, an enhancement of the World Wide Web, was developed in collaboration with GSI to cope with the huge amounts of data that occur during LHC experiments. During the commissioning of the accelerator GSI employees were directly involved likewise.

Linear accelerator
Ring accelerator
Inside the GSI's 120 meter long linear accelerator.
View into the tunnel of the ring accelerator.
G. Otto/GSI Helmholtzzentrum für Schwerionenforschung GmbH
A. Zschau/GSI Helmholtzzentrum für Schwerionenforschung GmbH