Heavy ion synchrotron and cooler-storage-ring in Lanzhou

The heavy-ion synchrotron complex HIRFL-CSR is a new cooler-storage-ring system in Lanzhou; it consists of a main ring (CSRm) and an experimental ring (CSRe). The existing cyclotron facility HIRFL is used as its injector system. The heavy ion beams from cyclotron with the energy of 7-25 MeV/u will be first injected into CSRm, accompanying with the cooling-accumulation and acceleration,finally extracted slowly with the energy of 500-1 000 MeV/u for external-target experiments, or extracted fast with the energy of 200-700 MeV/u to produce radioactive ion beams (RIBs) or high Z beams at the primary target of the beam line, and those secondary beams will be accepted and stored in CSRe for internal-target experiments. The HIRFL-CSR project was finished in 2006, and up to now all the commissioning activities and several experiments were made, including the stripping injection, multi-turn injection, cooling accumulation with hollow electron beam, ramping in the wide energy range with difference RF harmonic number, fast and slow extraction from CSRm, isochronous mode of CSRe, e-cooling for C-ion with the energy of 400 MeV/u, and the experiments of the RIBs mass-measurement in CSRe and the C-ion cancer therapy. (authors)