A method for solving X-ray spectra in laser fusion and a research on ponderomotive force

Two parts are inclued. (1) A method for solving X-ray spectra in laser fusion is presented. In order to solve X-ray spectra in laser fusion, an iterative method with amplitude-limiting and periodic smoothing technique has been developed on the basis of SAND iteration. It has been used to solve the X-ray spectra in laser fusion and some satisfactory results have been obtained. The method is suitable for solving the X-ray spectra from the data of sub-keV X-ray spectrometer, multi-channel K-edge filtering spectrometer and multi-channel filtering fluorescence spectrometer. The computational results show that the numerical instability is suppressed completely, and nonphysical 'negative spectra' and numerical structure in the computed X-ray spectra are eliminated by means of this method. The computational results are independent of the initial trial spectra. (2) Two-dimensional propagation of laser and ponderomotive force are studied. The authors have also studied the two-dimensional laser propagation code HEATER, which has been used in numerical research on absorption rate and radial and axial ponderomotive force with some proper modifications