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The \( N=28\) isotone 60Ge , \( T_{z}=-2\), was produced and selected among the products of the fragmentation reaction of a 78Kr beam at 150 MeV/nucleon and a Be target by means of the A1900 fragment separator at the National Superconducting Cyclotron Laboratory (NSCL) at Michigan State University (MSU). Its decay was studied for the first time using the optical time projection chamber. The \( \beta\)-decay of 60Ge was found to be dominated by \( \beta\)-delayed proton emission, with a branching of \( \approx 100\)% and half-life \( T_{1/2}=20_{-5}^{+7}\) ms.

Despite a lot of experimental and theoretical progress the question of the r-process site and the origin of the heavy elements in nature remains one of the biggest open questions in nuclear astrophysics. We report first results from experiments with rare isotope beams of r-process nuclei at Michigan State University’s National Superconducting Cyclotron Laboratory. This includes a first measurement of the half-life of the doubly-magic waiting point nucleus 78Ni, which serves as a major bottle-neck for the synthesis of heavy elements in many r-process models

The low energy level structure of neutron-rich 28,29Na has been investigated through β-delayed γ spectroscopy. The present work, which presents the first detailed spectroscopy of 29Na, clearly demonstrates that for Na isotopes between 28Na (N = 17) and 29Na (N = 18), intruder configurations start dominating the low lying excited states, suggestive of the small N = 20 shell gap.

The decay of the extremely neutron-deficient isotope 45Fe has been studied by using a new type of gaseous detector in which a technique of optical imaging is used to record tracks of charged particles. The two-proton radioactivity and the $ \beta$ -decay channels were clearly identified. For the first time, the angular and energy correlations between two protons emitted from the 45Fe ground state were measured. The obtained results were confronted with predictions of a three-body model.

Excited states in the neutron-rich 121, 123, 125Ag were studied via the fragmentation of a 136Xe beam at 120MeV/nucleon in a thick 9Be target. The levels in 121Ag were populated in the $ \beta$ decay of 121Pd while those assigned to 123, 125Ag were identified via isomer spectroscopy. The transitions identified in 121Ag are consistent with the $ \gamma$ -rays reported in 117, 119Ag . The newly observed transitions were placed in the level schemes of 123, 125Ag based on the analysis of $ \gamma$ - $ \gamma$ coincidences and the systematics. We attribute the onset of isomerism in the 123, 125Ag isotopes to the drop in energy of the negative-parity levels similar to the 5- state in the even-even Cd cores. The proposed level scheme for 125Ag is well described by the NuShellX shell model calculations.

An experiment was performed at the National Superconducting Cyclotron Laboratory at Michigan State University to investigate β decay of very neutron-rich cobalt isotopes. Beta-delayed neutron emission from 71–74Co has been observed for the first time. Preliminary results are reported.