The evolution of carbon-polluted white dwarfs at low effective temperatures

Understand

Taking advantage of the Gaia Data Release 2, recent studies have revisited the evolution of carbon-polluted white dwarfs (DQs) across a large range of effective temperatures.

• These analyses have clearly confirmed the existence of two distinct DQ evolutionary sequences: one with normal-mass white dwarfs and one with heavily polluted and generally more massive objects.
• The first sequence is thought to result from the dredge-up of carbon from the core, while the second could at least partially be made of descendants of Hot DQs.
• However, the evolution of carbon-polluted white dwarfs below 6500 K remains unexplored, mainly due to the theoretical difficulties associated with modelling their dense atmospheres.