How were the heavy elements created?

The chemical elements we find today on Earth and in the solar system were created throughout the history of the universe. Cosmic events and processes such as the Big Bang, the formation of stars, nuclear reactions, supernova explosions at the "end of life" of stars, and neutron stars and their mergers with each other have all contributed to this.

Since observing a neutron star collision by measuring gravitational wave signals and electromagnetic light curves, we know that in such events, our heaviest elements such as gold, are created in processes with very neutron-rich nuclei. These form complex reaction chains, in some cases involving hundreds of intermediate steps. Properties of such very neutron-rich nuclei, and thus also some properties of neutron stars, are studied at GSI and FAIR in various experimental facilities.

(Header: G. Otto/GSI/FAIR)