Conveners
Nuclear Physics
- Beatrice Franke (TRIUMF)
Nuclear Physics: Fundamental symmetries and Nuclear Structure
- Thomas Brunner (McGill/TRIUMF)
Neutron rich Mg isotopes far from stability belong to the island of inversion, a region where the single particle energy state description of the shell model breaks down and the predicted configuration of the nuclear states becomes inverted. Nuclei in this region also exhibit collective behaviour in which multiple particle interactions play a significant role in nuclear wavefunctions and...
At TRIUMF, Canada’s particle accelerator centre, the TIGRESS Integrated Plunger (TIP) and its configurable detector systems have been used for charged-particle tagging and light-ion identification in Doppler-shift lifetime measurements using gamma-ray spectroscopy with the TIGRESS array of HPGe detectors. An experiment using these devices to measure the lifetime of the $2^+_1$ state of...
Experiment S1758 aims to explore the charge dependence of the strong nuclear interaction by probing $^{55}$Ni and $^{55}$Co near the $\mathit{doubly}$ $\mathit{magic}$ $^{56}$Ni. This will be achieved by impinging beams of radioactive $^{20}$Na and stable $^{20}$Ne upon $^{40}$Ca targets to produce $^{55}$Ni and $^{55}$Co, respectively. Charged particles and $\gamma$-rays will be detected by...
The nuclear charge radius is a fundamental property of the nucleus, providing crucial information such as the emergence of deformation or unexpected "magicity". This structural information is paramount in probing the electroweak interaction, for example, through searches for atomic parity violation (APV) and electric dipole moments (EDM). Currently there are no experimentally measured absolute...
Molecules in which one or more of its constituting atoms contain a radioactive nucleus represent unexplored probes for new physics beyond the Standard Model of particle physics [1]. Radioactive atoms provide an additional degree of freedom to design molecular systems with, for instance, unmatched sensitivity to hitherto undiscovered permanent electric dipole moments (EDMs). Because of the link...
Precise tests of fundamental symmetries at low energy are an important tool for testing the Standard Model. Atomic parity violation (APV) measures the strength of highly forbidden atomic transitions induced by the parity violating (PV) exchange of Z bosons between electrons and quarks in heavy atoms. We are working towards measuring this effect in the heaviest alkali, francium, where the...
The breakdown of traditional magic numbers predicted by the shell model gives insight into the underlying nuclear interactions and acts as a test for existing models. Islands of inversion (IoI) in the nuclear landscape are characterized by the presence of deformed intruder ground states instead of the normal configurations predicted by the shell model. In the N=40 region, the relatively large...
Nuclei away from the line of stability have been found to demonstrate behavior that is inconsistent with the traditional magic numbers of the spherical shell model. This has led to the concept of the evolution of nuclear shell structure in exotic nuclei, and the neutron-rich Ca isotopes are a key testing ground of these theories; there have been conflicting results from various experiments as...
Understanding nuclear structure near 78Ni is crucial to infer how chemical elements originate in the Universe. State-of-the-art shell model calculations agree with observations from recent experiments regarding the persistence of the N = 50 shell closure in neutron-rich nuclei. How collectivity manifests and evolves in this region of the Segr ́e chart is still an open question, particularly...
