3D ray-tracing simulation of X-ray laser amplification

A 3D ray--tracing code has been developed to simulate the x-rays (λ = 139 A) produced in recent experiments where a silver target was driven by two laser beams. The code is used as a post-processor of the detailed kinetics code LASIX which provides emissivities and opacities for inverted transitions. The hydrodynamics of the plasma is calculated with the 1D1/2 CHIVAS code, where transverse profiles of temperatures and density follow a self-similar solution. Our 3D ray-tracing code accounts for progressive target illumination and calculates the x-ray laser output by solving the eikonal equation. Once 3D paths are determined a steady state transport solution is used to calculate the output intensity. The present 3D results are compared with 2D calculations as well as with collected experimental data.