We present a broad study of linear, clustered, noble gas puffs irradiated with the frequency doubled (527 nm) Titan laser at Lawrence Livermore National Laboratory. Pure Ar, Kr, and Xe clustered gas puffs, as well as two mixed-gas puffs consisting of KrAr and XeKrAr gases, make up the targets. Characterization experiments to determine gas-puff density show that varying the experimental parameter gas-delay timing (the delay between gas puff initialization and laser-gas-puff interaction) provides a simple control over the gas-puff density. X-ray emission (>1.4 keV) is studied as a function of gas composition, density, and delay timing. Xe gas puffs produce the strongest peak radiation in the several keV spectral region. The emitted radiation was found to be anisotropic, with smaller X-ray flux observed in the direction perpendicular to both laser beam propagation and polarization directions. The degree of anisotropy is independent of gas target type but increases with photon energy. X-ray spectroscopic measurements estimate plasma parameters and highlight their difference with previous studies. Electron beams with energy in excess of 72 keV are present in the noble gas-puff plasmas and results indicate that Ar plays a key role in their production. A drastic increase in harder X-ray emissions (X-ray flash effect) and multi-MeV electron-beam generation from Xe gas-puff plasma occurred when the laser beam was focused on the front edge of the linear gas puff.

中文翻译：

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研究高强度（7×10 19 W / cm 2）sub-ps激光束照射的纯净混合混合稀有气体泡芙，并在无激光的无碎片X射线源中实现强X射线闪光

我们在劳伦斯·利弗莫尔国家实验室以倍频（527 nm）泰坦激光照射线性，成簇的稀有气体泡芙进行了广泛的研究。目标由纯Ar，Kr和Xe簇状抽吸以及两个由KrAr和XeKrAr气体组成的混合气体抽吸组成。确定气孔密度的表征实验表明，改变实验参数的气延迟时间（气孔初始化和激光-气孔相互作用之间的延迟）可提供对气孔密度的简单控制。研究了X射线发射（> 1.4 keV）与气体成分，密度和延迟时间的关系。氙气抽吸在几个keV光谱区域产生最强的峰值辐射。发现发出的辐射是各向异性的，在垂直于激光束传播方向和偏振方向的方向上观察到的X射线通量较小。各向异性程度与气体目标类型无关，但随光子能量的增加而增加。X射线光谱测量可估算血浆参数，并突出显示它们与先前研究的差异。惰性气体等离子体中存在能量超过72 keV的电子束，结果表明Ar在其产生中起着关键作用。当激光束聚焦在线性气体抽吸的前边缘时，Xe气体抽吸等离子体产生的更硬的X射线发射（X射线闪光效应）和多MeV电子束急剧增加。X射线光谱测量可估算血浆参数，并突出显示它们与先前研究的差异。惰性气体等离子体中存在能量超过72 keV的电子束，结果表明Ar在其产生中起着关键作用。当激光束聚焦在线性气体抽吸的前边缘时，Xe气体抽吸等离子体产生的更硬的X射线发射（X射线闪光效应）和多MeV电子束急剧增加。X射线光谱测量可估算血浆参数，并突出显示它们与先前研究的差异。惰性气体等离子体中存在能量超过72 keV的电子束，结果表明Ar在其产生中起着关键作用。当激光束聚焦在线性气体抽吸的前边缘时，Xe气体抽吸等离子体产生的更硬的X射线发射（X射线闪光效应）和多MeV电子束急剧增加。