Analysis of plasma density profiles and thermal transport in laser‐irradiated spherical targets

Measurements are presented for plasma density profiles, critical surface trajectories, and mass‐ablation rates, as obtained from experiments in which layered spherical targets were irradiated with 1.05‐μm laser light at intensities between 1×101 4 and 1×101 5 W/cm2. The targets were designed to allow study of thermal transport in overdense plasmas. They were from 70 to 110 μm in diameter, with a variable thickness parylene ablator and an aluminum substrate. Simulated results are consistent with all three sets of data if transport of both thermal and suprathermal electrons is severely inhibited, with a flux limiter of 0.03≤f≤0.06 being appropriate.