Simulation of hard x-rays source produced by a picosecond laser irradiated solid target for Compton radiography
Abstract
A bremsstrahlung radiation hard x-ray source, produced by a picosecond intense laser irradiated solid target, was used to diagnose an implosion capsule at stagnation phase via Compton radiography in experiments. By performing Monte Carlo and particle-in-cell simulation, we investigated the influence of target materials and laser intensity on the >70 keV bremsstrahlung hard x-ray emission. We found that the brightness of the hard x-rays is proportional to the atomic number multiplied by area density (ZρL), which indicates that the higher Z and higher density gold or uranium material will produce the brightest hard x-rays source at the same thickness. In relativistic laser solid interactions, hot electron recirculation plays an important role in hard x-ray emission. Without recirculation, hard x-ray conversion efficiency decays when increasing the laser intensity. While the hard x-ray emission comes to the maximal saturated conversion efficiency at relativistic laser intensity if considering the electron recirculation. These results provide valuable insights into the experimental design of Compton radiography.
- Publication:
-
Plasma Physics and Controlled Fusion
- Pub Date:
- September 2020
- DOI:
- 10.1088/1361-6587/ab9a60
- Bibcode:
- 2020PPCF...62i5006L
- Keywords:
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- inertial confined fusion;
- Compton radiography;
- numerical modeling