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Chandra and FUSE spectroscopy of the hot bare stellar core H1504+65

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 LETG spectrum (60-160 Angstroem) shows a wealth of photospheric absorption lines from highly ionized oxygen, neon, and - for the first time identified in this star - magnesium and suggests 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 an O-Ne-Mg white dwarf.

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K. Werner, T. Rauch, M. A. Barstow, J. W. Kruk. 2004-04-16. Chandra and FUSE spectroscopy of the hot bare stellar core H1504+65. https://doi.org/10.1051/0004-6361%3A20047154

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