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Observations of the SW Sextantis Star UU Aquarii

D. W. Hoard·M. D. Still·Paula Szkody·Robert Connon Smith·D. A. H. Buckley
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Abstract

We present 14 nights of medium resolution (1-2Å) spectroscopy of the eclipsing cataclysmic variable UU Aquarii obtained during a high accretion state in 1995 August-October. UU Aqr appears to be an SW Sextantis star, as noted by Baptista, Steiner, & Horne (1996), and we discuss its spectroscopic behavior in the context of the SW Sex phenomenon. Emission line equivalent width curves, Doppler tomography, and line profile simulation provide evidence for the presence of a bright spot at the impact site of the accretion stream with the edge of the disk, and a non-axisymmetric, vertically- and azimuthally-extended absorbing structure in the disk. The absorption has maximum depth in the emission lines around orbital phase 0.8, but is present from $ϕ\approx0.4$ to $ϕ\approx0.95$. An origin is explored for this absorbing structure (as well as the other spectroscopic behavior of UU Aqr) in terms of the explosive impact of the accretion stream with the disk.

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D. W. Hoard, M. D. Still, Paula Szkody, Robert Connon Smith, D. A. H. Buckley. 1997-11-20. Observations of the SW Sextantis Star UU Aquarii. https://doi.org/10.1111/j.1365-8711.1998.01321.x

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