The US Rare Isotope Accelerator project

The Rare Isotope Accelerator (RIA) is a next generation radioactive beam facility in preparation in the US. RIA combines the best of standard ISOL and in-flight fragmentation technology with novel approaches to handle high-primary beam power and remove existing limitations in the extraction of short-lived isotopes. The use of a versatile primary accelerator (superconducting linac designed to allow multiple charge state acceleration and capable of providing beams from protons at 900 MeV to uranium at 400 MeV/u at power levels up to 400 kW) allows various production and extraction schemes to be used to optimize production of specific isotopes. In particular, a novel approach where radioactive isotopes produced by fragmentation of a fast heavy-ion beam are stopped and cooled in a high-purity helium gas cell and extracted by electromagnetic fields as thermal singly charged ions promises huge increases in efficiency for very short-lived isotopes. These isotopes will then be available for studies at ion source energy or can be further accelerated by a second superconducting linac whose novel injection system, based on CW low-frequency RFQs, allows the efficient acceleration of singly-charged heavy ions with masses up to 240 amu. from ion source energy. The high-intensity radioactive beams at RIA will be made available to four experimental areas spanning the energy regime from ion source energy to primary beam energy.