title: Diagnostic development in precise opacity measurement of radiatively heated Al plasma on Shenguang II laser facility.
abstract: Simultaneous measurements of the self-emission spectrum, the backlighting source spectrum, and the transmission spectrum in one shot, which reduce the experimental uncertainties from shot-to-shot fluctuation, are essential for precise opacity experiments. In order to achieve precise absorption spectrum of Al plasmas, a special half sample sandwich target was designed and short backlighter was used to provide time- and space-resolving diagnostics on the Shenguang II high power laser facility. In the measurement, a cylindrical cavity with CH foam baffles was used to provide a clean x-ray radiation environment for sample heating. The x-ray source spectrum, the transmission spectrum, and the self-emission spectrum of the soft x-ray heated Al sample were recorded in one shot with a penta-erythritol tetrakis (hydroxymethy) methane C(CH(2)OH)(4) (PET) crystal spectrometer by using the point-projection method. Experimental results have been compared with the calculation results of a detailed level accounting opacity code.
authors.affiliation: Wuhan National Laboratory for Optoelectronics, Institute of Optoelectronics Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, People's Republic of China. edwardszy@yahoo.com
authors.forename: Yang
authors.initials: Y
authors.lastname: Zhao
authors.forename: Jiamin
authors.initials: J
authors.lastname: Yang
authors.forename: Jiyan
authors.initials: J
authors.lastname: Zhang
authors.forename: Jinsong
authors.initials: J
authors.lastname: Liu
authors.forename: Xiao
authors.initials: X
authors.lastname: Yuan
authors.forename: Fengtao
authors.initials: F
authors.lastname: Jin