Targets for low-adiabat direct-drive-implosion experiments on OMEGA must meet rigorous specifications and tight tolerances on the diameter,wall thickness,wall-thickness uniformity,and presence of surface features.Of t...Targets for low-adiabat direct-drive-implosion experiments on OMEGA must meet rigorous specifications and tight tolerances on the diameter,wall thickness,wall-thickness uniformity,and presence of surface features.Of these,restrictions on the size and number of defects(bumps and depressions)on the surface are the most challenging.The properties of targets that are made using vapor-deposition and solution-based microencapsulation techniques are reviewed.Targets were characterized using confocal microscopy,bright-and dark-field microscopy,atomic force microscopy,electron microscopy,and interferometry.Each technique has merits and limitations,and a combination of these techniques is necessary to adequately characterize a target.The main limitation with the glow-discharge polymerization(GDP)method for making targets is that it produces hundreds of domes with a lateral dimension of 0.7-2 μm.Polishing these targets reduces the size of some but not all domes,but it adds scratches and grooves to the surface.Solution-made polystyrene shells lack the dome features of GDP targets but have hundreds of submicrometer-size voids throughout the wall of the target;a few of these voids can be as large as~12 μm at the surface.展开更多
Targets are an indispensable part of all inertial confinement fusion(ICF)and high-energy-density physics(HEDP)experiments:while a high-quality target does not guarantee the success of an experiment,a poor-quality one ...Targets are an indispensable part of all inertial confinement fusion(ICF)and high-energy-density physics(HEDP)experiments:while a high-quality target does not guarantee the success of an experiment,a poor-quality one can definitely lead to failure.In ICF and HEDP experiments,the precision with which targets are fabricated is critical to obtaining successful results,and many crossdisciplinary scientific and technological challenges are involved in the fabrication process.展开更多
基金This material is based upon work supported by the Department of Energy National Nuclear Security Administration under Award Number DE-NA0001944the University of Rochester,and the New York State Energy Research and Development Authority.
文摘Targets for low-adiabat direct-drive-implosion experiments on OMEGA must meet rigorous specifications and tight tolerances on the diameter,wall thickness,wall-thickness uniformity,and presence of surface features.Of these,restrictions on the size and number of defects(bumps and depressions)on the surface are the most challenging.The properties of targets that are made using vapor-deposition and solution-based microencapsulation techniques are reviewed.Targets were characterized using confocal microscopy,bright-and dark-field microscopy,atomic force microscopy,electron microscopy,and interferometry.Each technique has merits and limitations,and a combination of these techniques is necessary to adequately characterize a target.The main limitation with the glow-discharge polymerization(GDP)method for making targets is that it produces hundreds of domes with a lateral dimension of 0.7-2 μm.Polishing these targets reduces the size of some but not all domes,but it adds scratches and grooves to the surface.Solution-made polystyrene shells lack the dome features of GDP targets but have hundreds of submicrometer-size voids throughout the wall of the target;a few of these voids can be as large as~12 μm at the surface.
文摘Targets are an indispensable part of all inertial confinement fusion(ICF)and high-energy-density physics(HEDP)experiments:while a high-quality target does not guarantee the success of an experiment,a poor-quality one can definitely lead to failure.In ICF and HEDP experiments,the precision with which targets are fabricated is critical to obtaining successful results,and many crossdisciplinary scientific and technological challenges are involved in the fabrication process.