Foord M E, Heeter R F, van Hoof P A M, Thoe R S, Bailey J E, Cuneo M E, Chung H-K, Liedahl D A, Fournier K B, Chandler G A, Jonauskas V, Kisielius R, Mix L P, Ramsbottom C, Springer P T, Keenan F P, Rose S J, Goldstein W H
Lawrence Livermore National Laboratory, University of California, Livermore, CA 94551, USA.
Phys Rev Lett. 2004 Jul 30;93(5):055002. doi: 10.1103/PhysRevLett.93.055002. Epub 2004 Jul 29.
The charge state distributions of Fe, Na, and F are determined in a photoionized laboratory plasma using high resolution x-ray spectroscopy. Independent measurements of the density and radiation flux indicate unprecedented values for the ionization parameter xi=20-25 erg cm s(-1) under near steady-state conditions. Line opacities are well fitted by a curve-of-growth analysis which includes the effects of velocity gradients in a one-dimensional expanding plasma. First comparisons of the measured charge state distributions with x-ray photoionization models show reasonable agreement.
利用高分辨率X射线光谱法,在光致电离实验室等离子体中确定了铁、钠和氟的电荷态分布。对密度和辐射通量的独立测量表明,在近稳态条件下,电离参数ξ=20-25尔格·厘米·秒⁻¹的值前所未有的高。通过生长曲线分析很好地拟合了线透明度,该分析包括一维膨胀等离子体中速度梯度的影响。将测量的电荷态分布与X射线光电离模型进行的首次比较显示出合理的一致性。