The overview of the accelerator system for the facility for rare isotope beams at Michigan state university

The Facility for Rare Isotope Beams (FRIB) will accelerate stable beams of heavy ions to > 200 MeV/u with beam powers of up to 400 kW onto an in-flight fragmentation target to produce rare isotopes. The accelerator system will include a room-temperature front encl a double-folded superconducting driver linac and a beam delivery system. The front end will include superconducting ECR ion sources, a beam bunching system and a radio frequency quadrupole. The driver linac will include three acceleration segments using superconducting λ/4 and λ/2 cavities with frequencies of 80.5 and 322 MHz, and two 180 degree folding systems to minimize the cost of conventional construction. Charge-stripping and multi-charge state beam acceleration will be used for the heavier ions to increase acceleration efficiency. The beam delivery system will transport accelerated stable beams to the in-flight fragmentation target. End-to-end beam simulations have been performed to evaluate the performance of the driver linac. We will discuss recent progress in the accelerator design and the beam dynamics studies for the baseline accelerator system.