The HIRFL-CSR project was a national mega scientific project of China and was finished in the end of the 2007. After the finishing of HIRFL-CSR project, the HIRFL accelerator complex consists of two cyclotron (SFC, SSC) and two storage rings (CSRm, CSRe).

The injector system of SFC+SSC can provide all ions from proton to uranium. A variety of light to heavy ions, including C, Ar, Kr and Xe, have been accumulated and accelerated to the energy range of 235-1000MeV/u in CSRm. Besides a series of short lifetime nuclides mass measurement experiments and internal target experiments, the cancer therapy by heavy ion and hadron physics experiments are also performed in CSRm.

Due to many factors, it is very difficult to inject and accumulate the more heavy ions (mass number more than 200) in CSRm. One of the real challenges is the weak injected beam from cyclotron injector. The most critical point is to see the very first storage of the beam to tune the machine.

The accumulation and acceleration of the Bi beam is a key point for CSRm to realize the full ions' acceleration. During this dedicated machine study operation, ²⁰⁹Bi³⁶⁺  ion beam from superconducting Electron Cyclotron Resonance (ECR) ion source was accelerated to 1.96MeV/u by the cyclotron SFC. The low energy ²⁰⁹Bi³⁶⁺ extracted from SFC was transferred and injected into the main ring (CSRm) with MMI injection scheme supported by electron cooling. The gain factor of accumulation can reach 15 with injection beam about 2μA. It is a new record that heavy ion beam is accumulated and stored through accelerator complex of cyclotron and cooling storage ring combination.