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H1504+65 - The Naked Stellar C/O Core of a Former Red Giant Observed with FUSE and Chandra

K. Werner·T. Rauch·M. A. Barstow·J. W. Kruk
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Abstract

H1504+65 is an extremely hot hydrogen-deficient white dwarf with an effective temperature close to 200,000 K. We present new FUV and soft X-ray spectra obtained with FUSE and Chandra, which confirm that H1504+65 has an atmosphere primarily composed of carbon and oxygen. The Chandra spectra show a wealth of absorption lines from highly ionized oxygen, neon and magnesium and suggest relatively high Ne and Mg abundances. This corroborates an earlier suggestion that H1504+65 represents a naked C/O stellar core or even the C/O envelope of a O-Ne-Mg white dwarf.

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K. Werner, T. Rauch, M. A. Barstow, J. W. Kruk. 2002-05-06. H1504+65 - The Naked Stellar C/O Core of a Former Red Giant Observed with FUSE and Chandra. https://arxiv.org/abs/astro-ph/0205075

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