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A near-IR spectrum of the DO white dwarf RE J0503-285

Paul Dobbie·Matt Burleigh·Andrew Levan·Martin Barstow·Ralf Napiwotzki·Ivan Hubeny·.
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Abstract

We present a near-IR spectroscopic analysis of the intriguing DO white dwarf RE J0503-285. The IR spectrum fails to reveal evidence of the presence of a spatially unresolved, cool, late-type companion. Hence we have placed an approximate limit on the spectral-type and mass of a putative companion (later than M8, M<0.085Msun). This result rules out ongoing interaction between the white dwarf and a close companion with M>0.085Msun as responsible for the discrepancies between the observed photospheric abundances and model predictions. As the possibility remains that there is a cooler companion lying beyond the detection threshold of this study we use our modelling to estimate the improvement in sensitivity offered by a Spitzer observation.

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Paul Dobbie, Matt Burleigh, Andrew Levan, Martin Barstow, Ralf Napiwotzki, Ivan Hubeny, .. 2005-06-16. A near-IR spectrum of the DO white dwarf RE J0503-285. https://doi.org/10.1051/0004-6361%3A20053215

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