【摘要】 提出一种测量金激光等离子体电荷态分布与平均电离度的X射线光谱学诊断方法。该方法基于稳态碰撞-辐射近似,考虑电子离子直接碰撞激发与双电子复合两种激发态布居方式,建立了金M带5f-3d跃迁组辐射总强度与离子态分布的耦合方程。根据实验测量的金平面靶激光等离子体冕区辐射的5f-3d跃迁线系的强度分布,诊断得到了金激光等离子体的电荷态分布与平均电离度。此外,还分析了电子温度、电子密度以及双电子复合过程对电荷态分布及平均电离度诊断的影响,并将实验诊断结果与辐射流体力学理论模拟结果及离化平衡动力学计算结果进行了对比分析。结果表明:实验诊断结果与基于CRE近似的离化平衡动力学计算结果近似;当电子温度高于1.5 keV时,双电子复合过程对电离度的诊断结果影响较小。更多还原

【Abstract】 In this paper,a diagnostic method of average ionization degree by X-ray emission spectra of laser-produced gold plasma was presented.The coupled equations between the total intensities of 5f-3d transition arrays of gold M-band and the ion populations were set up based on steady collision-radiative equilibrium approximation,with electron-ion collisional excitation and dielectronic recombination being considered in the populations of exciting states.By the experimentally measured intensities of the 5f-3d transition arrays of gold ions,we deduced the distribution of charge states and average ionization degree of laser-produced gold plasma.Furthermore,we discussed the effects of electron temperature,electron density and dielectronic recombination on the diagnostics,and compared the diagnosed results with those of radiative-hydrodynamic simulations and ionization balance kinetics.更多还原