Ahlstrom H G
Appl Opt. 1981 Jun 1;20(11):1902-24. doi: 10.1364/AO.20.001902.
The progress of the LLNL Laser Fusion Program in our work to achieve high gain thermonuclear microex-plosions is discussed. Many experiments have been successfully performed and diagnosed using the large complex twenty-beam 30-TW Shiva laser system. A 400-kJ design of the twenty-beam Nova laser has been completed. The construction of the first phase of this facility has begun. The first phase of this Nd-doped low nonlinear index glass laser will consist of ten beams producing 100 kJ in 1-nsec pulses. One beam of the Argus laser has been converted to operation at 532 nm with 10-cm aperture. It will soon operate at 355 nm, also at 10-cm aperture. Frequency conversion crystals are being procured for full aperture operation at either 532 or 355 nm for both Argus beams. We also discuss new diagnostic instruments which provide us with new and improved resolution, information on laser absorption and scattering, thermal energy flow, supra-thermal electrons and their effects, and final fuel conditions. We have made measurements on the absorption and Brillouin scattering for target irradiations at both 1.064 microm and 532 nm. These measurements confirm the expected increased absorption and reduced scattering at the shorter wavelength. Additional data have been obtained on the angular distribution of suprathermal x rays, which further confirms our observation of its nonisotropy. However, we do not yet have an explanation of the phenomena. Implosion experiments have been performed which have produced final fuel densities over the 10-100x range liquid deuterium-tritium (DT) density. The 100x achievement is the highest yet achieved in laser fusion DT fuel targets.
讨论了劳伦斯利弗莫尔国家实验室激光聚变计划在实现高增益热核微爆炸方面的进展。利用大型复杂的二十束30太瓦希瓦激光系统成功进行并诊断了许多实验。二十束诺瓦激光的400千焦设计已经完成。该设施第一阶段的建设已经开始。这种掺钕低非线性折射率玻璃激光器的第一阶段将由十束激光组成,能在1纳秒脉冲内产生100千焦能量。阿格斯激光器的一束激光已转换为在孔径为10厘米的情况下于532纳米波长运行。它很快将在同样10厘米孔径下于355纳米波长运行。正在采购频率转换晶体,以使阿格斯激光器的两束激光能在532或355纳米的全孔径下运行。我们还讨论了新的诊断仪器,这些仪器为我们提供了新的、分辨率更高的信息,包括激光吸收和散射、热能流动、超热电子及其效应以及最终燃料状况。我们对1.064微米和532纳米波长下靶材辐照的吸收和布里渊散射进行了测量。这些测量结果证实了在较短波长下吸收增加和散射减少的预期。还获得了关于超热X射线角分布的更多数据,这进一步证实了我们对其非各向同性的观察。然而,我们尚未对这些现象作出解释。已经进行了内爆实验,产生的最终燃料密度比液态氘 - 氚(DT)密度高10至100倍。100倍的成果是激光聚变DT燃料靶材迄今取得的最高成果。