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Two delays in white dwarf evolution revealed by Gaia

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 نشر من قبل Sihao Cheng
 تاريخ النشر 2020
  مجال البحث فيزياء
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 تأليف Sihao Cheng




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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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