On Possible Oxygen/Neon White Dwarfs: H1504+65 and the White Dwarf Donors in Ultracompact X-ray Binaries
Abstract
We discuss the possibility to detect O/Ne white dwarfs by evidence for Ne overabundances. The hottest known WD, H1504+65, could be the only single WD for which we might be able to prove its O/Ne nature directly. Apart from this, strong Ne abundances are known or suspected only from binary systems, namely from a few novae, and from a handful of LMXBs. We try to verify the hypothesis that the latter might host strongly ablated O/Ne WD donors, by abundance analyses of the accretion disks in these systems. In any case, to conclude on O/Ne WDs just by strong Ne overabundances is problematic, because Ne enrichment also occurs by settling of this species into the core of C/O WDs.
- Publication:
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14th European Workshop on White Dwarfs
- Pub Date:
- July 2005
- DOI:
- 10.48550/arXiv.astro-ph/0410690
- arXiv:
- arXiv:astro-ph/0410690
- Bibcode:
- 2005ASPC..334..165W
- Keywords:
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- Astrophysics
- E-Print:
- 6 pages, to appear in "White Dwarfs", eds. D. Koester, S. Moehler, ASP Conf. Series