The Rosseland Mean Opacity of a Mixture of Gold and Gadolinium at High Temperatures

Radiation transport through high-opacity materials can be described using the Rosseland mean opacity of the medium, which is dominated by low-opacity regions in the frequency-dependent opacity. By mixing gold and gadolinium, we can fill in low-opacity regions of one material with high-opacity regions of another material, resulting in a material with a Rosseland mean opacity $1.5\ifmmode\times\else\texttimes\fi{}$ higher than either of the constituents. For a given laser energy, this can raise the temperature of the laser heated hohlraums, or for a given desired temperature, require less laser energy.