Polek Mathew, Harilal Sivanandan S, Hassanein A
School of Nuclear Engineering and Center for Materials under Extreme Environment, Purdue University, West Lafayette, Indiana 47907, USA.
Appl Opt. 2012 Feb 1;51(4):498-503. doi: 10.1364/AO.51.000498.
We performed two-dimensional (2D) mapping of the electron density in a laser-produced plasma with high spatial and temporal resolution. The plasma was produced by irradiating an aluminum target with 1064 nm, 6 ns pulses from a Nd:YAG laser under vacuum conditions. Stark broadening of the lines was used to estimate the electron density at various locations inside the plasma. The 2D spectral images were captured at different spatial points in the plasma using an imaging spectrograph coupled to an intensified CCD at various times during the plasma expansion. A comparison between radially averaged and radially resolved electron density profiles showed differences in the estimated values at the earlier times of plume evolution and closer distances to the target. However, the measured radially averaged values are consistent with 2D radial profiles at later times and/or farther distances from the target surface.
我们以高空间和时间分辨率对激光产生的等离子体中的电子密度进行了二维（2D）映射。该等离子体是在真空条件下，用钕钇铝石榴石激光器发出的1064纳米、6纳秒脉冲照射铝靶产生的。利用谱线的斯塔克展宽来估计等离子体内部不同位置的电子密度。在等离子体膨胀的不同时刻，使用与增强型电荷耦合器件相连的成像光谱仪，在等离子体的不同空间点捕获二维光谱图像。径向平均电子密度分布和径向分辨电子密度分布之间的比较表明，在羽流演化的早期以及距靶较近的距离处，估计值存在差异。然而，在后期和/或距靶表面较远的距离处，测得的径向平均值与二维径向分布是一致的。
