Bits and Pieces for the Nuclear Puzzle - Exploring light exotic nuclei with radioactive ion beams

Doktorsavhandling, 2016

Atomic nuclei are a fascinating case of many-body systems governed by quantum behaviour. This fact and the complex nuclear interaction are reasons why there is not yet a complete theory describing all atomic nuclei. Both experimental and theoretical efforts are needed to change this situation. Stable nuclei have been studied extensively, but more exotic nuclear systems are not yet well understood, and it is there where we expect to find improvements to our understanding of the complex nuclear interaction. Beams of light exotic nuclei have become accessible for experiments, and together with recent advances in detection systems, they open up possibilities for studying extreme nuclear systems up to and beyond the driplines, into the continuum. Experiments with light exotic beams deliver important data from extreme nuclear systems, which help to improve the description of atomic nuclei in general. This thesis is focused on light neutron-rich nuclei, and studies them in different ways. Proton-removal cross sections from boron and carbon isotopes are used to test the reaction model ABRABLA07. The agreement is surprisingly good, but the need for a better understanding of the induced excitation energy is demonstrated. Unbound nuclei beyond the dripline are produced via proton-knock-out reactions and studied. The data on the oxygen isotopes agree well with 3N-interaction shell-model calculations. The rare (β p) decay channel is observed in the halo nucleus 11Be. Nuclear reactions also play an important role in astrophysics and the question of how heavy elements are generated in our universe. Coulomb dissociation cross sections can be used to determine astrophysically important (n,γ) rates. Measured cross sections for 20N, 21N and 17C provide improved input for r-process network calculations.