On the evolution of ultra-massive white dwarfs

Understand

Ultra-massive white dwarfs are powerful tools to study various physical processes in the Asymptotic Giant Branch (AGB), type Ia supernova explosions and the theory of crystallization through white dwarf asteroseismology.

• Despite the interest in these white dwarfs, there are few evolutionary studies in the literature devoted to them.
• Here, we present new ultra-massive white dwarf evolutionary sequences that constitute an improvement over previous ones.
• In these new sequences, we take into account for the first time the process of phase separation expected during the crystallization stage of these white dwarfs, by relying on the most up-to-date phase diagram of dense oxygen/neon mixtures.