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arXiv · 1209.4977

Metal Abundances in Hot DO White Dwarfs

K. Werner·T. Rauch·E. Ringat·J. W. Kruk
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Abstract

The relatively high abundance of carbon in the hot DO white dwarf RE0503-289 indicates that it is a descendant of a PG1159 star. This is corroborated by the recent detection of the extremely high abundances of trans-Fe elements which stem from s-process nucleosynthesis in the precursor AGB star, dredged up by a late He-shell flash and possibly amplified by radiative levitation. On the other hand, the hottest known DO white dwarf, KPD0005+5106, cannot have evolved from a PG1159 star but represents a distinct He-rich evolutionary sequence that possibly originates from a binary white dwarf merger.

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K. Werner, T. Rauch, E. Ringat, J. W. Kruk. 2012-09-22. Metal Abundances in Hot DO White Dwarfs. https://arxiv.org/abs/1209.4977

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