Sudbury Neutrino Observatory Research at Laurentian University

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Laurentian University is one of five Canadian institutions that, along with collaborators from the United States and Great Britain, have designed, built, and now operate the Sudbury Neutrino Observatory (SNO) to solve an enduring enigma - the "solar neutrino problem." Neutrinos are fundamental particles created in large numbers by the nuclear reactions that fuel the sun. They interact with matter to only the slightest degree and the overwhelming majority escape the sun and radiate out traversing all obstacles. Measurements of the flux, of these solar neutrinos, are notoriously difficult and yet have been done by several independent techniques. For over thirty years these measurements have been at odds with the best calculated predictions. SNO has solved this problem by convincingly demonstrating that all of the predicted neutrinos are in fact present. The beauty of this solution is that SNO's measurements, all previous measurements, and the theoretical predictions are now consistent under a new picture in which neutrinos change their character as they travel. Previous experiments were only capable of detecting the unchanged neutrinos whereas SNO detected all neutrinos.    The researchers at Laurentian University are committed to advancing some of the base technologies that have played a large role in the success of SNO and that are certain to be crucial for next generation experiments. These extremely sensitive experiments demand the near elimination of radioactivity from the materials used in their construction and the ability to measure the miniscule amounts that remain. Pushing these frontiers of purity and sensitivity to radioactive contaminants is an enabling science for future experiments.    The SNO detector is also a uniquely sensitive instrument for the detection of neutrinos from supernovae. An exciting Laurentian responsibility within SNO is the operation of SNO's supernova trigger and its participation in the inter-experiment collaboration SNEWS (the Supernova Early Warning System) which would alert astronomers to a new galactic supernova actually in advance of the star having appeared to explode.