title: Two white dwarfs with oxygen-rich atmospheres.
abstract: Stars with masses ranging from 7 to 10 times the mass of the Sun end their lives either as massive white dwarfs or weak type II supernovae, but there are only limited observational constraints on either evolutionary channel. Here we report the detection of two white dwarfs with large photospheric oxygen abundances, implying that they are bare oxygen-neon cores and that they may have descended from the most massive progenitors that avoid core collapse.
authors: Department of Physics, University of Warwick, Coventry CV4 7AL, UK. Boris.Gaensicke@warwick.ac.uk
authors: B T
authors: BT
authors: Gänsicke
authors: D
authors: D
authors: Koester
authors: J
authors: J
authors: Girven
authors: T R
authors: TR
authors: Marsh
authors: D
authors: D
authors: Steeghs