Laser system to study exotic nuclear structure

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There are few properties more fundamental to the atomic nucleus than its shape and size. One of the most sensitive methods of probing and therefore examining the evolution of nuclear structure away from stability is to utilise the fact that the nucleus, by its very nature, interacts with the atomic electrons that surround it. High precision laser probing of the electrons energy invariably yields vast amounts of information in a model independent manner. This method is also one of the few ways available to obtain an absolute value for the spin of short lived nuclei, a parameter that is the basis upon which many nuclear models depend. These measurements can be made across almost the entire chart of the nuclides from the very lightest He and Li isotopes up to the heaviest elements that TRIUMF can provide. They also cover the entirety of nuclear structure from the stable, relatively spherical nuclei that occur along the valley of stability out to the extremes of deformation found towards the drip lines. Whilst in principle it is pure nuclear structure information that is deduced from these measurements the results have an influence in many other areas of physics being routinely used as either inputs, tests or support measurements. Topics where this information is used range from ab-initio calculations of nuclear forces in light nuclei to tests of the standard model of particle physics and the C.K.M. matrix unitarity out to investigations into non uniform distributions of nuclear magnetism within heavy nuclei for high precision Parity non-conservation experiments. The Laser Spectroscopy Collaboration at TRIUMF currently has eight of its own proposals accepted at TRIUMF as well as being a collaborator on several more. Of these eight six relied upon an ageing laser system at the heart of which is an Argon ion laser that is older than any of the students in the group. During the past year this system failed due both to old age as well as a reliance on over taxed cooling and power systems at TRIUMF. (The system requires over six gallons of water a minute passing through in order to remove over sixty kilowatts of excess heat.) This request is for a modern, all solid state laser system to replace the failed system and therefore permit the continued running of high impact experiments.