Improved and Tested: A New Generation of Cool White Dwarf Atmosphere Models

The photosphere of cool, helium-rich white dwarfs is notoriously tricky to model due to its fluid-like density. Using modern ab initio calculations, we have developed a new generation of atmosphere models that include an accurate description of the equation of state, chemical equilibrium and opacities under these high-density conditions. We show that our new models successfully fit objects that were poorly reproduced by previous models, notably those showing metal absorption lines.