Quantitative observation of monochromatic X-rays emitted from implosion hotspot in high spatial resolution in inertial confinement fusion

Kuan Ren,Jiamin Yang,Yudong Pu,Yulong Li,Shaoen Jiang,Yao-Yuan Liu ,Zhurong Cao,J F Wu ,Baozhong Mu,H Zhao ,Jun Yan ,Xiaoshi Peng,Yaran Li,Jiyan Zhang,Wei Jiang,Ke Lan,Tianxuan Huang,Jianjun Dong,Yongkun Ding,Tao Xu,Feng Wang

doi:10.1038/s41598-021-93482-4

Abstract

In inertial confinement fusion, quantitative and high-spatial resolution (< 10,upmu m) measurements of the X-rays self-emitted by the hotspot are critical for studying the physical processes of the implosion stagnation stage. Herein, the 8 ± 0.39-keV monochromatic X-ray distribution from the entire hotspot is quantitatively observed in 5-upmu m spatial resolution using a Kirkpatrick–Baez microscope, with impacts from the responses of the diagnosis system removed, for the first time, in implosion experiments at the 100 kJ laser facility in China. Two-dimensional calculations along with 2.5% P2 drive asymmetry and 0.3 ablator self-emission are congruent with the experimental results, especially for the photon number distribution, hotspot profile, and neutron yield. Theoretical calculations enabled a better understanding of the experimental results. Furthermore, the origins of the 17.81% contour profile of the deuterium-deuterium hotspot and the accurate Gaussian source approximation of the core emission area in the implosion capsule are clarified in detail. This work is significant for quantitatively exploring the physical conditions of the hotspot and updating the theoretical model of capsule implosion.

Highlights

In inertial confinement fusion, quantitative and high-spatial resolution (< 10 μ m) measurements of the X-rays self-emitted by the hotspot are critical for studying the physical processes of the implosion stagnation stage
This was achieved in implosion experiments performed at the 100 kJ laser facility of China[16,17]
We found that the calculated two-dimensional outline of the deuterium-deuterium hotspot is highly consistent with the 17.81% contour relative to the peak emission of the experimental results and that the core emission area of the experimental results could be accurately approximated as a Gaussian source

Summary

Introduction

Quantitative and high-spatial resolution (< 10 μ m) measurements of the X-rays self-emitted by the hotspot are critical for studying the physical processes of the implosion stagnation stage. Quantitative and high-space-resolving measurements of the physical conditions of the hotspot self-emitting area, which removes the impacts from the response of the diagnosis system, forms the foundation for further research on relative physical processes of the implosion stagnation stage in inertial confinement fusion (ICF)[1,2]. The 8 ± 0.39-keV monochromatic X-rays emitted by the hotspot were quantitatively measured with 5-μ m spatial resolution using an eight-image KB microscope[15] and, for the first time, without the impacts from the diagnosis system response. This was achieved in implosion experiments performed at the 100 kJ laser facility of China[16,17].

Methods

Findings

Conclusion