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arXiv · 1111.0555

Metal-Abundance Peculiarities in the sdOB Star EC11481-2303: A Progress Report

Ellen Ringat·Thomas Rauch
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Abstract

Spectral analyses of extreme horizontal branch (EHB) stars indicate a trend to supersolar heavy-metal abundances that is increasing with effective temperature. The sdOB EC11481-2303 is such a star, located at the very hot end of the EHB. In contrast to other sdOB stars, it is exhibiting an extraordinary flat UV continuum. This may be the result of extreme metal-line blanketing. We present preliminary results of a spectral analysis by means of static as well as stratified NLTE model atmospheres.

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Ellen Ringat, Thomas Rauch. 2011-11-02. Metal-Abundance Peculiarities in the sdOB Star EC11481-2303: A Progress Report. https://arxiv.org/abs/1111.0555

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