Characterization and optimization of a laser-produced x-ray source for x-ray radiography.

High-resolution x-ray radiography (HRXR) is a critical diagnostic tool for studying high-energy-density plasmas in large laser facilities such as the National Ignition Facility, the Laser Mega Joule, and Omega Extended Performance. However, geometric constraints in these facilities pose significant challenges for experimental design. This paper presents a comprehensive characterization of a picosecond laser-driven x-ray source tailored for HRXR applications. Through systematic experimental investigations, we analyzed the influence of various parameters on the performance of the x-ray source, focusing on spatial resolution and spectral distribution across a broad energy range. Our findings reveal that a single thin wire, comparable in diameter to the laser focal spot, positioned at 90° relative to the laser axis, serves as the optimal backlighter configuration. This configuration maximizes spatial resolution and spectral quality, addressing the geometric limitations inherent in large-scale laser facilities. The results provide a robust foundation for designing HRXR experiments, enabling more precise and reliable imaging of high-energy-density plasmas.