Experiments on the National Ignition Facility (NIF) to study hohlraums lined with a 20-mg/cc $400\text{−}\mu \mathrm{m}$-thick ${\mathrm{Ta}}_2{\mathrm{O}}_5$ aerogel at full scale (hohlraum diameter = 6.72 mm) are reported. Driven with a 1.6-MJ, 450-TW laser pulse, the performance of the foam liner is diagnosed using implosion hot-spot symmetry measurements of the high-density carbon (HDC) capsule and measurement of inner beam propagation through a thin-wall $8\text{−}\mu \mathrm{m}$ Au window in the hohlraum. Results show an improved capsule performance due to laser energy deposition further inside the hohlraum, leading to a modest increase in x-ray drive and reduced preheat due to changes in the x-ray spectrum when the foam liner is included. In addition, the outer cone bubble uniformity is improved, but the predicted improvement in inner beam propagation to improve symmetry control is not realized for this foam thickness and density.

中文翻译：

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国家点火装置上的泡沫衬里大直径惯性约束融合实验

国家点火装置（NIF）的实验研究内衬20 mg / cc的大头菜 $400\text{-}\mu \mathrm{米}$-厚 ${钽}_2{\mathrm{Ø}}_5$据报道全尺寸气凝胶（大直径= 6.72 mm）。在1.6-MJ，450-TW激光脉冲的驱动下，通过对高密度碳（HDC）胶囊的内爆热点对称测量以及通过薄壁的内部光束传播的测量来诊断泡沫衬里的性能。$8\text{-}\mu \mathrm{米}$在hohlraum的Au窗口。结果表明，由于激光能量进一步沉积在空穴内，胶囊的性能得到了改善，从而导致了X射线驱动力的适度增加，并且当包括泡沫衬里时，由于X射线光谱的变化，预热降低了。另外，外锥气泡的均匀性得到改善，但是对于这种泡沫厚度和密度，没有实现预期的内束传播的改善以改善对称性控制。