IRIS : Charged particle reaction spectroscopy at ISAC

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A large part of our universe is powered by nuclear reactions, that are the secret behind the glow of the sun and the shine of the stars. In our laboratories nuclear reactions and scattering are the ways to uncover the secrets that lie in the heart of visible matter in our universe. This project focuses on exploring the short-lived rare isotopes that are weakly bound located far from the valley of stability and many of which have a large excess of neutrons over protons or vice versa. Many of them are created in certain environments of our universe such as supernovae, neutron stars. New discoveries about their unknown properties become possible using rare isotope facilities in the world. Among them is the ISAC/ARIEL facility at Canada's particle accelerator center, TRIUMF that can produce low-energy re-accelerated beams of rare isotopes. The IRIS reaction spectroscopy facility utilizes these re-accelerated rare isotope beams to uncover new features of rare isotopes. IRIS has pioneered in the use of an thin frozen sheet of solid hydrogen as reaction target. The hydrogen isotope of the target interacts with accelerated beams of rare isotopes produced at TRIUMF. By observing the particles emitted from this interaction process using the silicon strip detectors and scintillators we can get a peek into the properties of rare isotopes. This reveals how nature arranges the building blocks to build these isotopes and hence deduce the properties of nature's strongest force (nuclear force). This also allows us to unravel how nature creates the majority of the heavy elements that we find on earth. The unexpected characteristics of these unstable nuclei make it necessary to seek answers to the fundamental question on how nature organizes the neutrons and protons to form a bound systems with highly asymmetric neutron to proton ratio and how do they behave at the limit when they become unbound.