In order to produce heavy-ion beams with velocities as large as ten percent or more of the velocity of light, it is far better, economically as well as technologically, to accelerate the ions in a multi-stepwise manner using accelerators in series rather than using a single large accelerator. The system of accelerators at RIKEN is a breed that is not seen anywhere else in the world.
In the case of relatively light heavy ions like carbon and nitrogen, the AVF cyclotron is most suitable for pre-accelerator; for very heavy ion like gold and bismuth, the linear accelerator is much more efficient in acceleration. Because of this, our accelerator system enables almost all ions of elements of the periodic table from hydrogen to uranium to be accelerated very efficiently.