Development of the HRIBF 25-MV tandem accelerator as a RIB accelerator

The Holifield facility 25URC tandem accelerator will begin accelerating radioactive ion beams (RIBs) for nuclear structure and astrophysics research in 1996. This paper addresses the development of the accelerator to allow optimum operation with the particular challengesassociated with RIBs. New diagnostics for ultra-low-intensity beams are being installed and the terminal potential stabilization system is being studied to optimize control with these low beam intensities. A new resistor-based voltage-grading system has resulted in more stable operation, as well as allowing operation at the very low terminal potentials which are required for some astrophysics experiments. Also addressed is beam transmission optimization, particularly at low terminal potentials, and operation of the accelerator at high terminal potentials.