Liquefication and crystallization of cooled relativistic ion beams

Properties of existing and planned cooled beams of intermediate energy ions are shown to be in the physical regime where a liquid or possibly a crystal may be formed. Thus these beams could provide a laboratory system for fundamental tests of many-body theory. An experimental test of the beam structure, involving scattering of laser light, is discussed. The experimental configuration used would provide continuously tunable coherent light over a wide frequency range when crystallization occurs. (orig.)