Study of M-band X-ray preheating effect on shock propagation via streaked optical pyrometer system at SG-III prototype lasers.

The M-band X-ray (1.6–4.4 keV) preheating and shock temperature of aluminum (Al) foil coated on a thick polystyrene (CH) layer is experimentally measured using a streaked optical pyrometer system (SOP) in the SG-III prototype laser facility for the first time. Multi-group hydrodynamic simulation captures the main characteristics of rear surface emission. Compared with the unpreheated target with bromine (Br) doped, M-band X-rays have a large impact on shock propagation inside the undoped target. Preheating changes target the initial state and generate a broader shock front, resulting in drastic variation in rear surface emission features. By comparing sensitivity analysis in the simulation and experimental uncertainty range, it is found that the SOP measurement could achieve valuable information on the shock transition time and unique emission profile, offering reliable boundary and benchmarks for simulation and analysis. Proper evaluation on the radiation source, including both the flux and the spectrum, and material opacities is essential for data interpretation. This study could promote our understanding and predictive capability required for inertial confinement fusion studies. [ABSTRACT FROM AUTHOR]