Grant: Subatomic Physics Envelope - Group

The atoms of all elements are composed of electrons orbiting a tiny massive core, the atomic nucleus. The nucleus is, in turn, composed of still smaller objects called protons and neutrons or, collectively, nucleons. These nucleons interact with each other by all of the known forces of nature, making the atomic nucleus an ideal "laboratory" for studying a wide range of topics of basic scientific interest, from the properties of the fundamental interactions of subatomic particles to how the nucleus as a whole behaves as a collective entity. To date, the use of the atomic nucleus as a laboratory for basic science research has been constrained by the small subset of the possible combinations of protons and neutrons (isotopes) found in nature. A great expansion of this field of science is, however, being made possible by the development of research facilities such as the Isotope Separator and Accelerator (ISAC) at the TRIUMF laboratory in Vancouver, British Columbia. ISAC produces world-record intensities of short-lived isotopes and delivers them to research scientists in the form of high-quality ion beams. In the present research, the high-frequency light (gamma rays) emitted when rare isotopes produced at ISAC decay or interact with other nuclei will be measured in state-of-the-art detector arrays known as the 8pi Spectrometer and TIGRESS, which have been designed and constructed by a collaboration of researchers from Canadian universities and TRIUMF. These measurements will support a broad program of basic science research, ranging from precision measurements of the weak interactions of subatomic particles called quarks to searches for the new interaction(s) required to account for the observed imbalance between matter and anti-matter in the universe, from studies aimed at a better understanding of how the chemical elements were synthesized in the explosions of stars to those trying to unravel how the atomic nucleus responds to the stresses of unusual neutron-to-proton ratios. The world leading combination of the ISAC facility and the sophisticated detection systems employed in these studies, will ensure that Canadian scientists remain at the forefront of the emerging field of rare isotope research.