Detailed diagnostics of a laser produced aluminum plasma by the K-alpha satellites

作者:Jin, Fengtao; Zeng, Jiaolong; Yuan, Jianmin*
来源:Journal of Quantitative Spectroscopy and Radiative Transfer, 2008, 109(16): 2707-2714.
DOI:10.1016/j.jqsrt.2008.06.004

摘要

A most recent measurement of the K. opacity of a laser produced aluminum plasma [Xu Y, Zhang J, Yang J, Pei W, Ding Y, Lai D, et al A clean radiation environment for opacity measurements of radiatively heated material. Phys Plasmas 2007;14:052701-5] has been theoretically studied by a detailed level accounting (DLA) model. The K-alpha lines both of Li-like and Be-like aluminum were calculated and used to perform detailed diagnostics to the plasma temperature. Atomic levels and oscillator strengths of the relevant ions were generated by solving the fully relativistic Dirac-Fock equation with configuration interaction within one-configuration being considered. Since the experimental plasma was well kept in local thermodynamic equilibrium (LTE), we solve the Saha equations to calculate the populations both between and within charge states. The aluminum plasma has reached so high a temperature of about 95eV that the populations of the Rydberg states of the Li-like and Be-like ions become considerably large and the K-alpha satellites become the dominating features. By best fitting to the measured spectrum the plasma temperature is determined to be 95 eV. However fairly large uncertainties of +/- 5eV are found.