Operation of the NSCL as a National User Facilty & Research Program

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This award provides funds to operate and maintain the National Superconducting CyclotronLaboratory (NSCL) at Michigan State University (MSU) as a national user facility, to support abroad program in nuclear structure, nuclear astrophysics, precision measurements of fundamentalparameters and symmetries, and accelerator science, and to support the research programs of MSUnuclear science faculty. The award will continue NSCL's national and international leadership inthese areas by supporting its operation as the nation's premier user facility dedicated to theproduction and study of rare (short-lived) isotopes. The award will also allow the NSCL to exploitthe scientific opportunities newly available with the recently commissioned and world-uniqueReA3 beamline accelerator that enables experiments at energies that have not been explored withrare isotopes and are relevant to supernovae and the structure of nuclei. These opportunities havestrong overlap with the stated scientific goals of the 2015 NSAC Long Range Plan, and form acoherent trajectory towards the next generation accelerator, FRIB, which is being constructed onthe NSCL site. Approximately 80% of those conducting research at the NSCL are from outsideMSU and the support of NSCL will serve a broad scientific community. As the nation's largestuniversity-based user facility for nuclear physics, the NSCL will continue to provide unique handsonlearning opportunities for educating the next generation of nuclear scientists, acceleratorphysicists, and engineers. Approximately 10% of all nuclear science PhDs awarded in the UnitedStates are based on research carried out at the NSCL, and approximately 100 undergraduatestudents are actively involved in research at the NSCL each year. The laboratory has extensiveoutreach activities, including facility tours for over 4000 people each year. In addition, researchis carried out in application areas such as development of new tools for radiation treatments ofcancer, systematic studies of how ionizing radiation affects DNA, discovery of novel atomic andnanostructures in complex materials, and homeland security.Intense beams of stable isotopes are accelerated using the NSCL's two coupled superconductingcyclotrons, the CCF. The nuclei split into fragments as the beam strikes a stationary target. Eachfragment is itself a lighter nucleus, and many fragments are themselves short-lived isotopes. Theisotope of choice for a specific experiment is selected by means of a fragment separator: a magneticchicane that permits only a specific charge and mass through its pathway. The nuclei emergingfrom the fragment separator form a new beam for use in studying various nuclear reactions. TheNSCL has seven end stations to where the isotope beam can be directed and each end station hasa variety of target and detector systems to carry out the desired measurements. The NSCL canalso bring the unstable isotopes to a complete stop using a dense gas; this in turn enablesexperiments such as mass measurements using trapping techniques also used in atomic andmolecular physics. The ReA3 beamline accelerator reaccelerates stopped isotopes to low energies(well below in-flight levels) for experiments that are important for nuclear astrophysics, includingthe origin of stellar energy production as well as the dynamics of the birth and death of stars. Thereaccelerated beams are directed to one of the end stations for use in various nuclear reactions.