KPD0005+5106: Hottest DO White Dwarf Much Hotter Than Assumed

K. Werner; T. Rauch; J. W. Kruk

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arXiv · 0710.4515

KPD0005+5106: Hottest DO White Dwarf Much Hotter Than Assumed

K. Werner·T. Rauch·J. W. Kruk

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Abstract

KPD0005+5106 is the hottest known helium-rich white dwarf. We have identified NeVIII lines in UV and optical spectra and conclude that it is significantly hotter than previously thought, namely Teff=200,000 K instead of 120,000 K. This is a possible explanation for the observed hard X-ray emission as being of photospheric origin. Concerning its evolutionary state, we suggest that KPD0005+5106 is not a descendant of a PG1159 star but more probably related to the O(He) stars and RCrB stars.

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K. Werner, T. Rauch, J. W. Kruk. 2007-10-24. KPD0005+5106: Hottest DO White Dwarf Much Hotter Than Assumed. https://arxiv.org/abs/0710.4515

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