Earlier nuclear accelerators fired beams of heavy nuclei at stationary metal targets.RHIC, in contrast, is a particle collider that crashes together two beams of heavy nuclei.

• 早期的原子核加速器，是用重原子核束轰击静止的金属靶，但RHIC并不一样，它是让两束重原子核互撞的粒子对撞机。