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arXiv · astro-ph/0610527

Discovery of a new cataclysmic variable through optical variability and X-ray emission

Magaretha L. Pretorius·Christian Knigge
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Abstract

Aims: We present discovery observations of the new cataclysmic variable star (CV) 1RXS J092737.4-191529, as well as spectra and photometry of SY Vol. The selection technique that turned up these two CVs is described; it should be efficient for finding dwarf novae with high outburst duty cycles. Methods: Two very common observational features of CVs, namely optical variability and X-ray emission, are combined to select targets for follow-up observations. Long-slit spectra were taken to identify CVs in the sample. Results: Two out of three objects selected in this way are CVs. One of these is the known dwarf nova SY Vol, while the second system, 1RXS J092737.4-191529, is a new discovery. We present medium resolution spectra, $UBVRI$ magnitudes, and high-speed photometry for both these CVs. Rapid flickering in the light curve of 1RXS J092737.4-191529 confirms the mass transferring binary nature of this object; it is probably a dwarf nova that was in quiescence during our observations.

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Magaretha L. Pretorius, Christian Knigge. 2006-10-17. Discovery of a new cataclysmic variable through optical variability and X-ray emission. https://doi.org/10.1051/0004-6361%3A20066418

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