Research

The IONAS group studies the structure and properties of exotic (short-lived) nuclei far from the valley of stability. These nuclei are produced in nature during the burning phase of stars in nuclear fusion processes or in a supernova explosion. In the laboratory, such nuclei are produced at large accelerator facilities, such as the fragment separator at GSI in Darmstadt or TITAN at TRIUMF in Vancouver.

Research on these nuclei is interesting for several reasons:
They can be used to test nuclear models and theories under new conditions. Many of these nuclei show quite astonishing properties not found in stable nuclei. These include the formation of neutron and proton "halos" or so-called neutron skins, i.e., dilute neutron density distributions at the nuclear surface. The discovery and study of such phenomena improves our understanding of nuclear physics, since conventional models do not correctly describe these structures and properties. A better understanding of the properties of exotic nuclei is also needed in astrophysics, for example, to understand element abundances in the solar system and the universe. With the fragment separator and storage ring at GSI, it is now possible for the first time to study exotic nuclei under conditions found in hot stellar matter.

The IONAS group studies the production of exotic nuclei at the fragment separator FRS and the SHIP at GSI in Darmstadt. It develops ion-optical separation techniques, mass spectrometers and detectors, and conducts experiments. These include precision mass measurements of exotic nuclei in the experimental storage ring ESR and at SHIPTRAP, and measurements of the half-life of highly charged ions.

The group is instrumental in the development of the Super-FRS superconducting fragment separator at the international Facility for Antiproton and Ion Research (FAIR).

It is also involved in instrumental developments and applications in analytical mass spectrometry within the LOEWE project AmbiProbe.