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arXiv · 2001.04483

Two delays in white dwarf evolution revealed by Gaia

Sihao Cheng
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Abstract

By comparing two age indicators of high-mass white dwarfs derived from Gaia data, two discoveries have been made recently: one is the existence of a cooling anomaly that produces the Q branch structure on the Hertzsprung--Russell diagram, the other is the existence of double-white-dwarf merger products. The former poses a challenge for white dwarf cooling models, and the latter has implications on binary evolution and type-Ia supernovae.

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Sihao Cheng. 2020-01-13. Two delays in white dwarf evolution revealed by Gaia. https://doi.org/10.1017/s1743921320000460

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