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arXiv · 2010.06120

Three-dimensional reconstruction of integrated implosion targets from simulated small-angle pinhole images

Shijian Li·Qiangqiang Wang·Xian Wei·Zhurong Cao·Qing Zhao
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Abstract

To indirectly evaluate the asymmetry of the radiation drive under limited measurement conditions in inertial confinement fusion research, we have proposed an integral method to approximate the three-dimensional self-radiation distribution of the compressed plasma core using only four pinhole images from a single laser entrance hole at a maximum projection angle of 10°. The simultaneous algebraic reconstruction technique (SART) that uses spatial constraints provided by the prior structural information and the central pinhole image is utilized in the simulation. The simulation results showed that the normalized mean square deviation between the original distribution and reconstruction results of the central radiation area of the simulated cavity was 0.4401, and the structural similarity of the cavity radiation distribution was 0.5566. Meanwhile, using more diagnostic holes could achieve better structural similarity and lower reconstruction error. In addition, the results indicated that our new proposed method could reconstruct the distribution of a compressed plasma core in a vacuum hohlraum with high accuracy.

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Shijian Li, Qiangqiang Wang, Xian Wei, Zhurong Cao, Qing Zhao. 2020-10-13. Three-dimensional reconstruction of integrated implosion targets from simulated small-angle pinhole images. https://doi.org/10.1364/oe.400778

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