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A Search for Unresolved Double Degenerates Using IUE Archives

Charles-Philippe Lajoie·Pierre Bergeron
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Abstract

We present preliminary results of a study aimed at detecting double white dwarf systems using a method based on a comparison of optical and UV spectra for 141 DA stars drawn from the IUE archives. In particular, we are looking for dicrepancies between optical and UV temperatures. Even though known unresolved degenerate binaries stand out in this comparison, most temperature differences can probably be attributed to the presence of reddening, or the presence of heavy elements. We are in the process of securing additional optical spectroscopic observations to increase the number of stars in our analysis.

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Charles-Philippe Lajoie, Pierre Bergeron. 2005-03-08. A Search for Unresolved Double Degenerates Using IUE Archives. https://arxiv.org/abs/astro-ph/0503191

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