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Paper: |
G87−7: A White Dwarf with a Strange Core Composition? |
Volume: |
372, 15th European Workshop on White Dwarfs |
Page: |
13 |
Authors: |
Fontaine, G.; Bergeron, P.; Brassard, P. |
Abstract: |
We present the results of an analysis of G 87−7, a DA star which has been previously suggested as a potential iron core white dwarf. This suggestion rests critically not only on the accuracy of the parallax measurements available for that star, but also on the accuracy of the atmospheric parameters deduced from optical spectroscopy. We therefore gathered additional high S/N ratio spectra for G 87−7 for the specific purpose of pinning down better its estimated atmospheric parameters. On the basis of these improved values of the effective temperature and surface gravity, we constructed families of full stellar models for G 87−7 assuming a variety of core compositions from pure C to pure Fe, and different envelope layering from 'thick' to 'thin'. We also considered the possibility that G 87−7 could be made, in part, of strange matter, an idea that has come out recently as an alternative to white dwarf cores with heavy elements. We report on some of the results of our calculations in this short communication. |
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