They are the smallest extraterrestrial and terrestrial worlds - in a gigantic laboratory, so to speak, and sometimes only for fractions of a second. Here the smallest particles are sent in streams on a collision course to create conditions that do not exist on earth - at a pace approaching the speed of light.
Researchers discover new chemical elements. They develop cancer therapies that have already saved the lives of patients who have already been treated and conduct basic research. This is possible with a particle accelerator at the GSI Helmholtz Center for Heavy Ion Research in Darmstadt south of Frankfurt/Main. And in the future, even more researchers from all over the world will have even greater opportunities.
The international accelerator facility "Fair" (Facility for Antiproton and Ion Research), one of the largest research projects in the world, is being built on a gigantic construction site in Darmstadt. A new acceleration ring with a circumference of 1.1 kilometers is currently being built there, in which ions, i.e. electrically charged atoms, held in check by gigantic magnets, can reach almost the speed of light in a vacuum. Regarding dimensions: In a vacuum, light travels almost 300,000 kilometers in one second.
According to the Scientific Director of GSI and "Fair", Paolo Giubellino, 1000 scientists per year have been able to carry out experiments here, in the future there will be around 3000. "Tens of thousands of researchers around the world have been trying here for years to get opportunities for experiments."
What is special about "Fair" is that it offers very broad research opportunities. This is not the case with the much larger particle accelerator LHC of the European Organization for Nuclear Research (Cern) in Geneva, which only recently went back into operation. There is a much narrower focus there, says Giubellino, who himself experimented at Cern.
With the new ring, which according to current plans should be completed in 2027, and the existing GSI facility, there will then be two ring and one linear accelerator on the site. The chemical elements can then be accelerated to 285,000 kilometers per second before being sent to the laboratories for experiments.
"The linear accelerator is something like first gear in the car," says GSI spokesman Ingo Peter. In the rings, they are then kept on track by magnets in a beam channel and accelerated further and further. "The system is the only one in the world that can accelerate all elements."
Scientists also discover new elements here. "If one nucleus hits another in the center, a new atomic nucleus can form," says GSI spokeswoman Jutta Leroudier. "Elements found in this way have to be confirmed in other laboratories." Then they have to be recognized by an independent body.
Six new elements have already been detected here. Today they are in the periodic table under the atomic numbers 107 to 112. Temperatures, pressures and densities can be generated that only occur in the universe,” says Peter. “Together with our experiments, one can then understand phenomena of the universe.
With house-sized detectors, the scientists want to solve the mystery of mass in basic physical research. “The concept of mass has not yet been clarified. It's about understanding how parts are built, how mass mechanisms work," says Leroudier. Several hundred researchers are working on the puzzle of how the total mass comes about. According to the Helmholtz Center, one of the large detectors generates magnetic fields that are so strong that they could be used to lift 480 tons of iron.
In cooperation with the European space agency Esa, research is also being carried out for missions in space. "We want to investigate the radiation risks of manned missions and the possible risks for the material as well," says Leroudier. According to Peter, from 1997 to 2008 deeper brain tumors were also treated with the linear accelerator.
450 patients who had already been treated were shot at with pinpoint accuracy with ion beams and the tumors were thus killed - a therapy that is now used to treat patients in clinics in Heidelberg and Marburg and others abroad. "We're developing the therapy here," says Peter. Something like this is also being considered for tumors in movable organs or for cardiac arrhythmias.
External research groups have to finance their experiments themselves. The infrastructure is provided on site. In the case of requests for experiments, a panel assesses the relevance and then makes a recommendation. The experimental operation is currently suspended. However, materials such as high-performance magnets are tested for "fair". In addition, a new modern control center and an energy-efficient data center about six floors high are being built to process the expected huge amounts of data. According to GSI, more than five billion arithmetic operations per second can be achieved here.
According to the Federal Ministry of Research, the current budget is around 3.1 billion euros, which is significantly higher than when construction began. 17 years ago, a necessary budget of 1.3 billion euros was assumed. Due to the corona pandemic, the development of building material prices and disrupted global supply chains, an external assessment was carried out in 2021, which, however, could not yet take into account the war in Ukraine.
Inflation, the war, Corona and delivery bottlenecks: The technical director of GSI and "Fair", Jörg Blaurock, is certain that the budget will not stop there. “There will have to be a cost increase. That is to be expected given the overall situation,” says the specialist for large-scale construction projects. In addition, cooperation with Russia was frozen because of the sanctions. Russia should primarily supply magnets. These are replaceable, there is no technologically critical situation. And his managing director colleague Giubellino is certain that scientific principles that will lead to Nobel prizes can later be researched at the facility.
The construction of the “Fair” particle accelerator in Darmstadt is a gigantic project. According to "Fair" and the GSI Helmholtz Center for Heavy Ion Research, around two million cubic meters of earth have to be moved for the construction, as much as for 5000 single-family houses.
600,000 cubic meters of concrete are being used, which would be enough for eight football stadiums in Frankfurt. In addition, 65,000 tons of steel are used, about the amount for nine Eiffel Towers. Construction began in 2007. The centerpiece will be the underground ring accelerator with a circumference of 1.1 kilometers and shielded by thick concrete walls.