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arXiv · 1107.4790

A Far Ultraviolet Spectroscopic Analysis of BZ Ursae Majoris

P. Godon·E. M. Sion·B. T. Gaensicke·D. deMartino
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Abstract

We present an analysis of the Hubble Space Telescope/Space Telescope Imaging Spectrograph (HST/STIS) far ultraviolet snapshot spectrum of the dwarf nova BZ UMa taken during quiescence. We find that the flux continuum is consistent with that of a white dwarf atmosphere with a temperature of 15,000K, and a distance of about 156pc when assuming a white dwarf gravity of log(g)=7.5. We also show that the hydrogen quasi-molecular satellite lines opacity affects the spectrum around 1300-1400 A and has to be included to fine-tune the spectral modeling, this is self-consistent with the low stellar temperature we find.

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P. Godon, E. M. Sion, B. T. Gaensicke, D. deMartino. 2011-07-29. A Far Ultraviolet Spectroscopic Analysis of BZ Ursae Majoris. https://doi.org/10.1086/661763

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