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arXiv · 1701.05222

Hubble Space Telescope Cosmic Origins Spectrograph Spectroscopy of the Southern Nova-like BB Doradus in an Intermediate State

Patrick Godon·Edward Sion·Boris Gansicke·Ivan Hubeny·Domitilla de Martino·Anna Pala·Pablo Rodriguez-Gil·Paula Szkody·Odette Toloza
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Abstract

We present a spectral analysis of the Hubble Space Telescope Cosmic Origins Spectrograph spectrum of the southern VY Scl nova-like variable BB Doradus, obtained as part of a Cycle 20 {\it HST/COS} survey of accreting white dwarfs in cataclysmic variables. BB Dor was observed with {\it COS} during an intermediate state with a low mass accretion rate, thereby allowing an estimate of the white dwarf temperature. The results of our spectral analysis show that the white dwarf is a significant far ultraviolet component with a temperature of $\sim$35,000-$\sim$50,000$~$K, assuming a $0.80~M_{\odot}$ WD mass ($\log(g)=8.4$). The disk with a mass accretion rate of $\approx 10^{-10}~M_{\odot}~$yr$^{-1}$ contributes about 1/5 to 1/2 of the far ultraviolet flux.

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Patrick Godon, Edward Sion, Boris Gansicke, Ivan Hubeny, Domitilla de Martino, Anna Pala, Pablo Rodriguez-Gil, Paula Szkody, Odette Toloza. 2017-01-18. Hubble Space Telescope Cosmic Origins Spectrograph Spectroscopy of the Southern Nova-like BB Doradus in an Intermediate State. https://doi.org/10.3847/1538-4357%2F833%2F2%2F146

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