The impact of non-ideality effects in dense plasma on the evolution of white dwarfs

Recently made possible observations of cool and faint white dwarfs using the Gaia and other telescopes provide rich material for refining the modeling of the final stage of their evolution, which in turn can be used to study the behavior of matter under extreme conditions. In this paper, we simulate the thermal evolution of white dwarfs for different atmospheric compositions using equations of state for non-ideal dense plasma. By taking into account the effects of non-ideality in the code for the evolution of white dwarfs, it is possible to reach the stage of crystallization at the center of the star. The subsequent acceleration of cooling is significant for massive white dwarfs ($M \approx 1.3$ $M_{\odot}$), for which the cooling time at $T_{\rm eff} \approx 3 \times 10^3$ K decreases almost 10 times compared to the calculation without non-ideality effects.