STRUCTURE OF 3-D COULOMB CRYSTAL DEPENDING ON OUTER ENVIRONMENT

带负电的微粒在等离子体中被正离子包围而结晶。这种晶体有望应用于实际晶体中物理现象的分析，但由于重力和离子流的各向异性作用，晶体的三维结构难以形成。因此，本研究尝试在微重力条件下形成三维库仑晶体，并对细颗粒的行为进行分析。利用抛物飞行实验装置对细粒子等离子体进行了微重力实验，分析了微重力条件变化下细粒子的有序性和行为。微重力条件下细颗粒沿径向排列，重力条件下细颗粒沿垂直方向排列。有人认为，在重力作用下，正离子流和负离子流的相互影响导致了细粒子的垂直排列和离子随等离子体变形而向细粒子的垂直流动。因此，细粒子等离子体是自组织的，因此注射细粒子的方法应该影响细粒子的排列。虽然没有达到在同位素力场中形成三维库仑晶体的最终目标，但这一新发现对未来研究的发展应该是有用的。

Negatively charged fine particles in a plasma are surrounded by positive ions and is crystallized. such a crystal is expected to be applied to the analyses of physical phenomena in a real crystal, however the formation of 3-d structure of the crystal is difficult due to the anisotropic forces by gravity and ion flows. Therefore, under microgravity, a 3-D Coulomb crystal was tried to be formed and the behavior of fine particles were analyzed in this research.Microgravity experiments of fine-particle plasma were carried out by the use of a drop experiment facility and parabolic flights, and fine-particle ordering and behavior have been analyzed in the change of gravitational conditions. Fine particles aligned in radical directions were observed under microgravity, while they were aligned in the vertical direction under gravity. It has been suggested that under gravity the mutual influence between positive ion flow and negative fine particles results in the vertical alignment of fine particles and the vertical flow of ions toward fine particles along with the deformation of plasma. Thus fine particle plasmas are self-organized, so that the method of injection of fine particles should affect the arrangement of fine particles. Although the final goal that is the formation of a 3-D Coulomb crystal in a isotopic force field was not achieved, the new finding should be useful for the development of the research in future.