Laser Cooling of Relativistic Li-like O5+ Ion Beams at Heavy-ion Storage Ring CSRe

摘要

Laser cooling is one of the most promising techniques to achieve high phase-space densities or even crystalline beams for relativistic heavy ion beams at storage rings[1].Based on the success of laser cooling of C3+at the ESR[2;3],and the experience of test laser cooling experiments at the CSRe[4],laser cooling of lithium-like O5+ion beams with an relativistic energy of 275.7 MeV/u was achieved for the first time at the heavy-ion storage ring CSRe in Lanzhou,China.In the experiment,a CW laser system with a wavelength of 220 nm was used to match the optical transition of 2s1=2-2p1=2 of O5+ions.In order to cool the relativistic ion beams with only one counterpropagating CW laser,the ion beams were bunched by applying a sinusoidal voltage to the RF-buncher system.Fig.