Controlled non-neutral-plasma experiment on fundamental processes in transport and relaxation to equilibrium states of a many-charged-particle system.

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Major achievements of this project are summarized in three categories :(1) Experimental analysis of vortex dynamics in terms of two-dimensional (2D) turbulence :Spectral analyses are carried out on the vortex structures appearing during the relaxation of unstable initial density distribution of a magnetized pure electron plasma. The ensemble of guiding centers of electrons is morphologically equivalent to 2D fluid and its density is proportional vorticity. Increasingly fine structures in the low-density population in the real space represent cascading in the wave-number space, downward in energy and upward in enstrophy. [JPSJ (2006), Phys.Rev.E (2007)](2) Experimental and theoretical analyses of wave-induced transport :Rotating Trivelpiece-Gould mode wave is identified to strongly induce the radial transport of magnetized electrons. The radial drift is associated with the axial acceleration of resonant electrons so that the radial transport and the axial heating represent two paths of Landau-damping wave energy. Predictions of the quasi-linear theoretical model are quantitatively confirmed on the observational basis. [Phys.Plasmas (2005, 2006)](3) Construction of 3D distribution of an equilibrium pure electron plasma in a Penning trap :Fast scheme for the 3D distribution from observed 2D image data is successfully applied to reveal fine structures in a low-density population surrounding a high-density core distribution. The potential distribution of self-field is skillfully utilized to evaluate the electron temperature approaching the room temperature only by extracting less than 1% of total particles. [Phys.Plasmas (2006)]