Cold antimatter for quantum state-resolved precision measurements | Science & Technology

After the Big Bang more than 13 billion years ago, the universe was full of high-energy radiation, which constantly generated pairs of matter and antimatter particles such as protons and antiprotons. When such a pair collides, the particles are annihilated and converted into pure energy again. So, all in all, exactly the same quantities of matter and antimatter should be generated and annihilated again, meaning that the universe should be largely matterless as a consequence.

However, there is clearly an imbalance — an asymmetry — as material objects do exist. A minuscule amount more matter than antimatter has been generated — which contradicts the standard model of particle physics. Physicists have therefore been seeking to expand the standard model for decades. To this end, they also need extremely precise measurements of fundamental physical parameters.

This is the starting point for the BASE collaboration (“Baryon Antibaryon Symmetry Experiment”). It involves the universities in Düsseldorf, Hanover, Heidelberg, Mainz and Tokyo, the Swiss Federal Institute of Technology in Zurich and the research facilities at CERN in Geneva, the GSI Helmholtz Centre in Darmstadt, the Max Planck Institute for Nuclear Physics in Heidelberg, the National Metrology Institute of Germany (PTB) in Braunschweig and…