Spectroscopy of exotic nuclei at the NSCL: Tracking the nuclear shell structure with direct reactions

Alexandra Gade, , National Superconducting Cyclotron Laboratory, Michigan State University

The quest to comprehend the properties of short-lived, radioactive nuclei - referred to as "exotic nuclei" or "rare isotopes" - drives experimental and theoretical research programs worldwide. The nuclear potential and the resulting shell structure are fairly well established for stable nuclei. However, far from the valley of β stability, the large neutron excess and reduced binding toward the neutron drip line can lead to dramatic changes in the nuclear structure. Unexpected modifications of the structure of exotic nuclei have already been found: the development of new magic numbers and the breakdown of shell gaps that are established in stable nuclei. Well-established experimental techniques used for decades to study stable nuclei are not applicable at the low beam rates encountered for the most exotic isotopes. Powerful new precision techniques have been developed to enable in-beam spectroscopy studies of fast rare-isotope beams with intensities three of four orders of magnitude less than needed for the established low-energy techniques. Recent results from nuclear spectroscopy experiments performed at the National Superconducting Cyclotron Laboratory at Michigan State University will be presented.