The Rare Isotope Accelerator, or RIA, is a proposed particle accelerator meant to produce and study short-lived nuclear isotopes. In addition to studying the properties of nuclei with extreme neutron-to-proton ratios, the hope is that RIA will provide a better understanding of the formation of heavy elements in extreme astrophysical environments like the outer layers of an exploding supernova.
Similar research is currently being done at the Isotope Separation and ACceleration (ISAC) experiment at Canada's TRIUMF laboratory. Compared to ISAC, RIA would have a higher primary-beam power (which would provide higher intensities) and a more flexible combination of ion sources (which would provide a wider variety of rare isotopes to study).
In 2006, RIA was put on hold by the United States Department of Energy, in order to focus its budget on existing accelerator projects.
* RIA web page at Michigan State University
* RIA web page at Argonne National Laboratory