Nuclear-Reaction Mechanisms


Research program of the Nuclear-Reaction Mechanisms group is devoted to high-resolution measurements of nuclear-reaction products, aimed to bring a wider understanding of the reaction mechanisms involved in nucleus-nucleus and nucleon-nucleus collisions in the GeV energy regime. Detailed understanding of reaction mechanisms is of importance for basic reasearch as well as for different applications. 

The installations of GSI provide unique conditions for these types of studies: Experiments in inverse kinematics enables measuring of complete nuclide distributions and establishing the reaction kinematics, overcoming many limitations of conventional experiments.  

Intense efforts for systematically providing nuclear data have a long tradition. Right after the discovery of nuclear fission, the determination of neutron-capture cross sections of different materials and the yields of prompt and delayed fission neutrons established the basic knowledge for the development of nuclear technology. Practically all nuclear data, important for the design of conventional fission reactors, have been experimentally determined. Plans for modern developments of nuclear plants like the accelerator-driven system (ADS) and planning of future Radioactive-Ion-Beam (RIB) facilities for fundamental research changed the situation drastically: Due to the extension of the energy range up to 1 GeV, it has become impossible to provide all relevant nuclear data by dedicated experiments. Instead, a different approach has to be taken, according to which some experiments provide key information for a number of well selected cases, which are used for developing appropriate codes, for covering the whole field. Therefore, these experiments should not only provide high-quality data but also enable a very good understanding of the physics behind nucleon-nucleus and nucleus-nucleus collisions.  

In order to have proper description of physics behind nucleon-nucleus and nucleus-nucleus collisions, good knowledge on different static and dynamic properties of nuclear matter is mandatory. Nuclear structure effects in fission and fragmentation, nuclear fission from highly excited nuclei, interaction between fireball and spectators, isospin (N/Z) physics have to be well understood if one wants to make reliable predictions. 

The work is embadded in a larger international collaboration, named CHARMS (Collaboration for High-Accuracy Experiments on Nuclear Reaction Mechanisms with magnetic Spectrometers).