Simulation study on transverse laser cooling and ordering of heavy-ion beams in a storage ring

Yuri, Yosuke

The molecular dynamics approach with the stochastic interaction effect between laser photons and ions is employed to study the formation of three-dimensionally ultralow-temperature ion beams by means of laser cooling in a storage ring. The efficiency of three-dimensional (3D) laser cooling of a coasting beam was investigated by the combination of horizontally-displaced lasers and resonant coupling at several different operating points. It was found that the indirect transverse cooling efficiency depended on the displacement and detuning of the lasers as well as on momentum dispersion. A string crystalline state of the beam was attained at low line density by 3D cooling. At higher line density, on the other hand, 3D ordered structures was formed depending on laser-cooling conditions.