Nuclear Physics Group


Figure 1 : Schematic of the Isotope Separator and Accelerator (ISAC) radioactive ion beam facility at TRIUMF.

TRIUMF is Canada's national laboratory for nuclear and particle physics research and one of the world's leading subatomic physics research laboratories. It is home to the Isotope Separator and Accelerator (ISAC), the world's highest power radioactive ion beam facility of the isotope separation on-line (ISOL) type. High intensity beams of rare isotopes are produced at ISAC when the atomic nuclei of a primary target material are broken apart by an intense (up to 100 μA) beam of high-energy (500 MeV) protons delivered by TRIUMF's main cyclotron (the largest in the world). These rare isotopes, some of which exist for only thousandths of a second before they decay, are ionized and mass separated before being delivered as high-quality ion beams to a wide variety of experimental facilities at ISAC, where they support a diverse program of nuclear structure, nuclear astrophysics, fundamental symmetries, and materials science research. In addition to experiments with low energy (30-60 keV) radioactive ion beams, the ISAC facility is also capable of re-accelerating the radioactive beams, first to energies between 0.15 and 1.7 MeV/nucleon with a radio frequency quadrupole (RFQ) and room temperature drift-tube linear (DTL) accelerator and, subsequently, up to 6.5 - 15 MeV/nucleon (depending on the nuclear mass number) through the ISAC-II superconducting linear accelerator. A major expansion of the ISAC facility, the new $96M Advanced Rare IsotopE Laboratory (ARIEL), is currently under construction and will add both a high-power superconducting electron linear accelerator for rare isotopes production through photofission reactions in actinide production targets and the capability to deliver three simultaneous radioactive beams to the experimental facilities at ISAC, ultimately tripling the available rare isotope beamtime.

Our group at the University of Guelph leads research with two major gamma-ray spectrometers at ISAC, the GRIFFIN Spectrometer for low-energy decay spectroscopy research at ISAC-I and the TIGRESS spectrometer for experiments with the accelerated radioactive beams provided by ISAC-II. We have also lead the development of an innovative new neutron detector array (DESCANT) for use at both ISAC-I and ISAC-II and have recently received funding from the Canada Foundation for Innovation (CFI), the Ontario Ministry of Research and Innovation (MRI) and, in partnership with collaborators from Simon Fraser University, the British Columbia Knowledge Development Fund (BCKDF) to complete a second phase of the GRIFFIN spectrometer that will further enhance its signal-to-background response.