This work focuses on the evolution of single-particle structure in a region of the nuclear chart rich with exotic nuclear structure. The author has led the analysis of the ²⁸Mg(d,p)²⁹Mg reaction, measured with the ISOLDE Solenoidal Spectrometer (ISS) at the ISOLDE facility, CERN. This was the first measurement made using this device and the first time that a solenoidal spectrometer has been used at an ISOL radioactive beam facility. Significant attention is paid to optimizing methods of analysing direct nuclear reactions taking place in solenoidal fields and, as part of this, the author has developed his own analysis codes and simulations. The thesis gives an extremely comprehensive and well-written description of this novel system and provides a canonical reference for ISS that will be of great use to researchers and students, as well as presenting some significant scientific results focused on the N=20 "island of inversion", a region of nuclides of great current interest in nuclear physics.

Patrick T. MacGregor is a nuclear-structure physicist, probing exotic nuclear systems primarily using transfer reactions. He completed his PhD in experimental nuclear physics at The University of Manchester in 2021, investigating the single-particle structure of the neutron-rich 29Mg, the results of which are written in this volume. This details the results from the first experiment at the ISOLDE Solenoidal Spectrometer (ISS), a novel device at the CERN facility that is able to study exotic nuclear systems. This work was published in Physical Review C 104, L051301 (2021). He is an experienced user of this device, and has supported other experimental campaigns that use it (see, for example, T. L. Tang et al., Physical Review Letters 124, 062502 (2020)).

Currently, he is pursuing postdoctoral research using transfer reactions to extract the occupancies and vacancies of the A=124 neutrinoless double beta decay system. Additionally, he is continuing his research on the magnesium isotopes by analysing data from an analagous reaction performed at the ISS to investigate the single-particle structure of 31Mg. Outside of work, he enjoys spending time with his wife, Ally, who has brought colour to his otherwise boring lifestyle.