The X-ray properties of Al plasmas were studied experimentally by using the excimer laser facility in the State Key Laboratory of Laser Interaction with Matte. Radiated fluxes were recorded within two X-ray diodes, and the relative spectral distributions were recorded within an X-ray flat-field grating spectrograph, respectively. Experimental results indicated that the major X-ray photons were between 60 eV and 360 eV. By employing the spectral integration method, the measured data were appropriately processed to obtain absolute energies of the X-ray that radiated from Al plasmas.
Laser drive ramp compression is an important way to achieve extremely high pressure but relatively low temperature material state. This article introduces our progresses in recent years. The main progresses contain theoretical researches and experimental researches. In theoretical part, an analytical model for designing driving pressure pulse was set up, and a new characteristic method based on a Murnaghan-form state equation was developed. What’s more, X-ray preheating in the target and laser pulse design in laser-indirect-driven experiments were studied. In the experimental part, laser-direct driven experiments and laser laser-indirect driven experiments were performed on aluminum and iron, results showing the experimental design methods were feasible, and the compressions were in isentropic ways.
K-shell spectra of a laser-produced carbon plasma have been measured and analyzed. A graphite plate was irradiated by a 2.1ns ultraviolet laser pulse, and the radiated X-rays were measured with a flat-field grating spectrograph. The recorded lines have been identified as hydrogenic Lyman series 1s-np and heliumlike transitions 1s2 -lsnp (n=2-4). The measured wavelength and the spectral resolution of the flat-field grating spectrograph were calibrated by utilizing those lines. Hydrodynamic simulations and calculations of charge-state distributions in the local thermodynamic equilibrium (LTE) regime were carried out to interpret the K-shell spectra.