Single-particle foundations of nuclear structure
The single-particle framework of nuclei is encapsulated in the hugely successful shell model of nuclei. By using reactions that selectively add and remove individual protons or neutrons, we can reveal underlying single-particle properties. This technique is now being applied to short-lived nuclei.
Fission and heavy-ion fusion
The break-up of heavy nuclei or the fusing together of lighter ones continues to yield surprising results. For example, the process of fusion between nuclei has been found to be strongly suppressed at energies below the Coulomb barrier, in violation of conventional theories. High-precision, low-background measurements are essential to measure these very low probability reactions.