We demonstrate high conversion efficiency for extreme ultraviolet (EUV) emission at 6.5–6.7 nm from multiple laser beam-produced one-dimensional spherical plasmas. Multiply charged-state ions produce strong resonance emission lines, which combine to yield intense unresolved transition arrays (UTAs) in Gd, Tb, and Mo. At an optimum laser intensity of 1 × 1012 W/cm2, which is estimated to yield an electron temperature of around 100 eV, the maximum in-band EUV conversion efficiency (CE) was observed to be 0.8%, which is one of the highest values ever reported due to the reduction of plasma expansion loss.

The beam neutralization system for measurement of the spatial and velocity distributions of alpha particles of ITER plasmas was studied. As forward angle detection against the beam injection direction is required for effective neutralization, arrangement of the measurement system using possible ports in ITER configuration is proposed. The count rate of neutralized alpha particles produced by the double charge exchange interaction with energetic He0 beam particles injected is estimated. The ratios of signal to neutron-induced noise are evaluated. When a He0 beam produced by autodetachment from a 1–1.5MeV He− beam of 10mA is injected, the signal to noise ratio becomes greater than 1 at ρ<0.4, even without beam modulation. Usage of a lock-in technique at the frequency of radio-frequency quadrapole accelerator will make measurement at the outer region possible.

Low-density foams irradiated by a 20 kilojoule laser at the Omega laser facility (NY, USA) are shown to convert more than 5% of the laser energy into 4.6 to 6.0 keV x rays. This record efficiency with foam targets is due to novel fabrication techniques based on atomic-layer-deposition of Ti atoms on an aerogel scaffold. A Ti concentration of 33 atomic % was obtained in a foam with a total density of 5 mg/cm 3 . The dynamics of the ionization front through these foams were investigated at the 1 kilojoule laser of the Gekko XII facility (Japan). Hydrodynamic simulations can reproduce the average electron temperature but fail to predict accurately the heat front velocity in the foam. This discrepancy is shown to be unrelated to the possible water adsorbed in the foam but could be attributed to effects of the foam micro-structure.

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We have developed a time-of-flight analyzer to measure energy distributions of reflected particles from solid surfaces bombarded by low-energy (1–2keV) ions. The analyzer yields energy distributions of neutrals which can be compared with the energy distributions of charged particles measured by a magnetic deflection-type momentum analyzer. We have tested the system to measure the angular dependence of energy and intensity for neutrals reflected from a polycrystalline W target. The energies of the reflected neutrals are much smaller than the incident ion energies, suggesting multiple scattering in the target. No angular dependence is observed under the condition that the sum of the incident and reflected angles is constant. The intensity of the reflected neutrals takes the maximum around the mirror angle. We compare these characteristics of neutral particle reflections with those of reflected ions.