We investigated the intermittent convective plasma transport in a attached and⁄or detached plasma condition of the linear divertor plasma simulator, NAGDIS-II. Images taken by a fast-imaging camera clearly show that in attached plasmas, blobs are peeled off the bulk plasma, and propagate outward with an azimuthal motion. In detached plasmas, plasma turbulence observed near the plasma recombining region drives strong intermittent radial plasma transport, which could broaden the radial density profile.

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A highly space-resolved Thomson scattering system installed on the large helical device revealed that the electron temperature profile of the plasma occasionally has bulged regions at the location where the iota is close to 1.

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H-mode-like discharge was found in LHD with a full B_t field of 2.5 T at an outwardly shifted configuration of R_ax = 4.00 m where the m⁄n = 1⁄1 rational surface is located at the ergodic layer. The H-mode-like discharge was triggered by changing the P_NBI from 9 MW to 5 MW in a density range of 4-8 × 10¹³ cm^-3, followed by a clear density rise, ELM-like H_α bursts, and a reduction of magnetic fluctuation. These H-mode-like features vanished with a small radial movement of the 1⁄1 surface.

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Plasma-Based Ion Implantation and Deposition (PBII&D) has been developed for surface modification of three dimensional materials immersed in plasma. The ions are implanted into the material to which a train of pulsed voltage are directly applied so as to make an ion sheath around the surface of the material. During the ion implantation, plasma species and their compound materials are simultaneously deposited on the materials. This is a cost-effective and simple surface modification system. Conformal ion implantation can be carried out by this method. Metallic arcs such as cathodic arc and gas discharges using organic metallic gas have been used. In addition to the negative bias application system for extracting positive ions, positive pulse application system to extract electrons to heat the materials and positive pulsed bias method have been also developed. As industrial applications, the surface modification of inside pipes by PBII&D is introduced.

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Production mechanism of spontaneous plasma flow and flow velocity shear in the toroidal plasma is described. The plasma flow parallel to the magnetic field is produced by the radial electric field through the viscosities in the plasma. The observation of plasma flow driven by the thermodynamic force such as pressure gradient are presented. The effect of flow velocity shear on the transport, which determines the pressure profiles, is also discussed.

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The effects of ion flow velocity shears parallel and perpendicular to the magnetic-field lines, which are precisely controlled by a segmented electrode, are investigated in open-ended magnetized plasmas. The perpendicular flow velocity shears are demonstrated to suppress drift-wave, flute, and ion-cyclotron instabilities. On the other hand, parallel flow velocity shears are observed to destabilize D’Angelo mode, drift-wave, and ion-cyclotron instabilities depending on the sign of the parallel shear. The combined effects of the parallel and perpendicular flow shears will be important for controlling instabilities in magnetized plasmas.

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The plasma flow velocity shear instability, the so-called Kelvin-Helmholtz (K-H) instability has recently been recognized as an important process for the mass and energy transport of solar wind plasma into the earth magnetosphere. Even though this has been supported by many in-situ plasma observations, its physical mechanisms are still controversial. Recently, progress was made by a MHD simulation in which non-linear coupling with secondary instabilities results a turbulent and broad mixing layer. In the present paper, a new Sun-Earth connection model is proposed in which the K-H instability plays an important role.

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Vortex formation and the role of flow velocity shear are considered in a magnetized plasma with finite viscosity. The essential difference between a viscous-vortex and an inviscid-vortex is the existence of a radial flow, which transfers the vorticity into the core to be balanced with the diffusion due to viscosity. It is concluded that the formation of a viscous vortex (a stationary localized structure of vorticity) is generally possible in plasmas having finite viscosity.

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Recent modeling efforts on the radiation damage over multi-time scales are summarized. Under irradiation, materials experience multiple physical processes such as collision, cooling, thermalization and diffusions that extend over vast range of temporal scales. Correspondingly, modeling of these processes requires different schemes efficient for evaluation on each scale. The main outcome of individual process is obtained by utilizing the various methods, such as binary collision approximation, molecular dynamics, kinetic Monte Carlo, and rate theory. The remaining key issue to overcome is how to establish a methodology for passing information between the models and how to maintain the physical consistency.

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A new research project on extreme ultraviolet(EUV) source development has been started utilizing resources of laser fusion research. The main task of the project is to provide a scientific basis for generating efficient, debris-free, high power EUV plasma source for production of semiconductor devices. Spherical solid-tin targets were illuminated uniformly with twelve beams from GEKKO XII to create spherical plasmas, and EUV emission spectra were absolutely measured. The highest conversion efficiency of 3 % to 13.5 nm EUV light in 2 % bandwidth was attained at irradiance of around 5×10¹⁰W⁄cm². The experimental data were well reproduced by a theoretical model taking power balance in the EUV plasma into consideration.

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