Performance evaluation of a novel scintillation-based x-ray imager for the national ignition facility

Experimental validation of multi-scale hydrodynamics codes requires precise measurements of shock-driven instabilities. We have developed an experimental platform for radiographically observing shock wave interactions, with material interfaces featuring pre-imposed sinusoidal perturbations. In these shock tube experiments, shock fronts cross the perturbed boundary, driving hydrodynamic instabilities that evolve toward turbulence. At the National Ignition Facility (NIF), strict energy and geometric constraints demand backlit imagers with spatial resolution better than 5 microns over a 600-micron field of view. We successfully designed a novel X-ray detector that achieves high spatial resolution and signal-high signal-to-noise ratio by combining a CsI(Tl) scintillator with a magnifying optical system. This detector was integrated with a laser-driven X-ray source and a curved crystal microscope. We have achieved a quantum efficiency of 36.4% at 7.2 keV with 5 ± 0.5 micron resolution at the object plane. Our novel scintillation-based x-ray imager will allow us to take high resolution radiographs to validate multi-scale hydrodynamics codes.