Abstract
Gold disk targets were irradiated using focusing and beam smoothing methods on Xingguang (XG-II) laser facilities with 350 nm wavelength, 0.6 ns pulse width and 20–80 Joules energies. Laser absorption, light scattering and X-ray conversion were experimentally investigated. The experimental results showed that laser absorption and scattered light were about 90% and 10%, respectively, under focusing irradiation, but the laser absorption increased 5%–10% and the scattered light about 1% under the condition of beam smoothing. Compared with the case of focusing irradiation, the laser absorption was effectively improved and the scattered light remarkably dropped under uniform irradiation; then due to the decrease in laser intensity, X-ray conversion increased. This is highly advantageous to the inertial confinement fusion. However, X-ray conversion mechanism basically did not change and X-ray conversion efficiency under beam smoothing and focusing irradiation was basically the same.
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Jiang, S., Zhang, B., Liu, S. et al. Experiments and analysis of gold disk targets irradiated by smoothing beams of Xingguang II facilities with 350 nm wavelength. Sci. China Ser. G-Phys. Mech. Astron. 50, 716–730 (2007). https://doi.org/10.1007/s11433-007-0069-z
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DOI: https://doi.org/10.1007/s11433-007-0069-z