Absorption of Bound States in Hot, Dense Matter.

Shepherd, R. ; Audebert, P. ; Chenais-Popovics, C. ; Geindre, J. P. ; Fajardo, M. ; Iglesias, C. ; Moon, S. ; Rogers, F. ; Gauthier, J. C. ; Springer, P.

Technical Information Center Oak Ridge Tennessee

关键词: Strongly coupled plasma;    Opacity;    Short pulse laser;    Streak cameras;    X-ray sources;   

RP-ID  :  DE200515013264

学科分类：工程和技术（综合）

美国|英语

来源: National Technical Reports Library

【 摘 要 】

Preliminary experiments using a long pulse laser generated X-ray source to backlight a short pulse laser heated thin foil have been performed at the Laboratoire pour lutilisation des Lasers Intenses (LULI) at Ecole Polytechnique in France. In these experiment, a 2 J, 300 ps, 532 nm laser was used to create the X-ray back-lighter. The primary diagnostic was a von Hamiss spectrograph coupled to a 500 fs X-ray streak camera (TREX-VHS) developed at LLNL - This diagnostic combines high collection efficiency (approx. 10(sup -4) steradims) with fast temporal response (around 500 fs), allowing resolution of extremely transient spectral variations. The TFWXVHS was used to determine the time history, intensity, and spectra3 content of the back-lighter. The second diagnostic, Fourier Domain Interferometry (FDI), provides information about the position of the critical density of the taxget and thus the expansion hydrodynamics, laying the ground work for the plasma characterization. The plasmas were determined to be moderately to strongly coupled, resulting in absorption measurements that provide insight into bound states under such conditions.