Neon Cluster Formation and Phase Separation during White Dwarf Cooling

  title={Neon Cluster Formation and Phase Separation during White Dwarf Cooling},
  author={Matthew E. Caplan and C. J. Horowitz and Andrew Cumming},
  journal={arXiv: Solar and Stellar Astrophysics},
Recent observations of Galactic white dwarfs (WDs) with Gaia suggest there is a population of massive crystallizing WDs exhibiting anomalous cooling -- the Q branch. While single-particle $^{22}$Ne sedimentation has long been considered a possible heat source, recent work suggests that $^{22}$Ne must separate into clusters, enhancing diffusion, in order for sedimentation to provide heating on the observed timescale. We show definitively that $^{22}$Ne cannot separate to form clusters in C/O WDs… Expand

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