Indirectly driven low-convergence-ratio implosion experiments are conducted on SGIII prototype laser facility. Neutron yield, ion temperature and bangtime, and also their variation laws with the increase of ablator thickness are measured. These results are analyzed quantitatively and qualitatively, and the difference between the measurements and the calculations is discussed. The degradation of neutron yield is attributed to the hydrodynamic instabilities and implosion asymmetries.

Resonance lines are extensively used to diagnose electronic temperature T, and ions distribution. However, the analysis of the x-ray spectroscopy emitted from plasmas produced by a ns laser isually needs the help of a code or some assumptions. In this paper, a diagnostic idea of using line-pairs emitted from a doubly-excited state is proposed. By using the method presented in this paper, T, and the fractional population ratio of bare nuclei and H-like ions are directly obtained from the emission intensity ratios.

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The plastic DD filled capsule implosion experiment is performed on Shenguang III prototype laser facility. One-dimensional hydrodynamic numerical simulations show that the implosion compression ratio can be controlled by changing the capsule ablator thickness. In experiments, two types of capsules are studied and most of important implosion parameters are collected, such as neutron yield, X-ray bang-time, trajectory, and shape of hot core. The comparison between post-simulations and experimental results is performed. In our experiments, the neutron yield is 6.8×107 and YOC1D reaches 34% for low compression ratio implosion; the neutron yield is 6.3×106 and YOC1D is only 2.3% for middle compression ratio implosion. Meantime, the shape of hot core obtains an extra higher Legendre partial (P2 is 18% and P4 is 5%). On another side, the trajectory and bang-time are compared with simulations well.