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Many efforts have been made in nuclear structure physics to interpret the nature of low-lying excited 0+ states in well-deformed rare-earth nuclei. However, one of the difficulties in resolving the nature of these states is that there is a paucity of data. In this work, excited 0+ states in the N = 92 nucleus 160Er were studied via the 162Er(p, t)160Er two-neutron transfer reaction, which is ideal for probing 0+ → 0+ transitions, at the Maier-Leibnitz-Laboratorium in Garching, Germany. Reaction products were momentum-analyzed with a Quadrupole-3-Dipole magnetic spectrograph. The 0+2 state was observed to be strongly populated with 18% of the ground state strength.

The β-decay half lives of nuclei near the r-process path are critical information required for abundance calculations, especially those near neutron number N = 82. Specifically, the nuclei below doubly-magic 132Sn are key, and play an important role in the formation and shape of the second r-process abundance peak. The half lives in this region are challenging to measure due to the significant β-delayed neutron decay branches and the population of isomeric states with half lives comparable to the ground states. However, by measuring the time distribution of γ rays, these complications can be eliminated. This requires, however, a very effcient γ-ray spectrometer since the production of isotopes in this region is very limited. The new GRIFFIN array at TRIUMF-ISAC provides the high effciency required for these measurements. Recent improvements in the quality of the beams produced at TRIUMF, employing the IG-LIS device, are outlined, as well as the current status of the ARIEL facility. The GRIFFIN spectrometer and its use are briefly described. The experiment to measure the half lives of 128-130Cd is outlined and the results given, and some examples of the power of GRIFFIN to expand decay schemes, specifically for the decay of 128Cd to 128In, are given.

This work reports on the scattering of 11Be on 197Au at energies around and below the Coulomb barrier. By experimentally identifying the elastic scattering, inelastic scattering and breakup channels, and comparing them with different calculations, valuable information on the 11Be structure and its B(E1) distribution to the continuum are obtained. On top of that, a deeper understanding of the scattering process at low energies is achieved for reactions of this kind, making these studies extendable to other loosely-bound systems like 17,19C

The nuclear structure of 122Xe has been investigated with measurements of the β+/EC decay of 122Cs with the 8 π γ-ray spectrometer at the TRIUMF-ISAC facility. The data collected have enabled the determination of relative B(E2) values of some low-energy transitions, and the in-band transitions of the excited 0+ bands have been observed. As a result, the 2+ rotational band members for the 0+2 and 0+3 states have been firmly identified.

The DESCANT array (Deuterated Scintillator Array for Neutron Tagging) consists of up to 70 detectors, each filled with approximately 2 liters of deuterated benzene. This scintillator material o_ers pulse-shape discrimination (PSD) capabilities to distinguish between neutrons and γ-rays interacting with the scintillator material. In addition, the anisotropic nature of n – d scattering allows for the determination of the neutron energy spectrum directly from the pulse height spectrum, complementing the traditional time-of-flight (ToF) information. DESCANT can be coupled either to the TIGRESS (TRIUMF-ISAC Gamma-Ray Escape Suppressed Spectrometer) γ-ray spectrometer [1] located in the ISAC-II [2] hall of TRIUMF for in-beam experiments, or to the GRIFFIN (Gamma-Ray Infrastructure For Fundamental Investigations of Nuclei) γ-ray spectrometer [3] located in the ISAC-I hall of TRIUMF for decay spectroscopy experiments.

A neutron tagging array based upon liquid deuterated scintillators is being developed for the study of neutron-rich systems. The DEuterated SCintillator Array for Neutron Tagging, or DESCANT, will serve as an auxiliary detector for both the TIGRESS and GRIFFIN γ-ray spectrometers located at TRIUMF’s ISAC radioactive ion beam facility. DESCANT is comprised of 70 pseudohexaconical detectors of five varieties. The array is fully close-packed, subtends a downstream angle of θ = 65° and covers 92.6% of this solid angle or 1.08π sr. Each detector is 150 mm thick and filled with Bicron BC-537 liquid deuterated scintillator. The white, red and blue detectors are viewed by 127 mm diameter Hamamatsu R4155 photomultiplier tubes while the yellow and green detectors are viewed by 78 mm diameter ET Enterprises 9822B photomultiplier tubes. The aim of this work is to report on the mechanical design of DESCANT and the performance of a prototype detector measured using mono-energetic neutrons.

A study of the 110In β+/EC decay was performed at the TRIUMF Isotope Separator and Accelerator (ISAC) facility to probe the nuclear structure of 110Cd. The data were collected in scaled-down γ-ray singles, γ − γ coincidence, and γ-electron coincidence mode. The data were sorted and a random-background subtracted γ − γ matrix was created containing a total of 850 million events. We expanded the level scheme of 110Cd significantly by identifying 75 levels under 3.8 MeV, including 12 new ones, and increased the number of previously observed transitions from these levels to 273. The γ-ray branching intensities have been extracted through an analysis of the coincidence intensities. The branching ratios were combined with a reanalysis of lifetimes measurements obtained in an (n, n'γ) reaction with monoenergetic neutrons for the calculation of B(E2) values and these results have lead to the proposal of a γ-soft rotor, or O(6) nucleus, rather than a vibrational, or U(5) pattern for the nature of the low-lying, low-spin levels in 110Cd.

A new ancillary detector system for the TIGRESS HPGe array called SPectrometer for Internal Conversion Electrons (SPICE) is currently under development. SPICE consists of a segmented electron detector, photon shield and a permanent magnetic lens. SPICE will enable in-beam electron spectroscopy and, in coupling to the TIGRESS HPGe array, coincident gamma-electron spectroscopy with stable and radioactive beams.