High Energy Laser Preheat Characterization for MagLIF Experiments

Laser preheating is used in Magnetized Liner Inertial Fusion (MagLIF) experiments to set the fuel adiabat before the pulsed-power driven implosion. In previous experiments and simulations, it has been shown that the laser-fuel coupling is strongly influenced by the pre-imposed axial magnetic field, the laser spot size, and the presence of the laser entrance hole (LEH) window. Experiments were conducted at the Omega laser facility and at the Z-machine with the goal of characterizing laser-fuel coupling at MagLIF relevant conditions. The Z-machine laser preheat platform closely matched the integrated MagLIF experiments and used an argon dopant to enable X-ray imaging and spectroscopic analysis. The Omega experiment used a gas-puff target which allowed access for optical diagnostics and the option to include or exclude a surrogate LEH window. Comparisons are made against three-dimensional HYDRA calculations for both experiments.



SNL is managed and operated by NTESS under DOE NNSA contract DE-NA0003525.