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arXiv · 1603.01410

The Kepler and Hale observations of V523 Lyr

E. Mason·S. B. Howell
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Abstract

We present new observations of the cataclysmic variable V523 Lyr, a member of the open cluster NGC 6791. The Kepler Space telescope obtained photometric observations of this source and we examine the nearly 3 year long light curve. The observations show numerous small amplitude outbursts recurring on average every 33 days, intermittent quasi-periodic oscillations, and a significant fully coherent period of ~3.8 hr which we identify as the orbital period of the binary. Contemporaneous optical spectroscopy of V523 Lyr reveals a faint blue source with broad Balmer absorption lines containing narrow emission cores. H$\alpha$ is in emission above the continuum. The low amplitude of the photometric signal and no detected velocity motion suggest a low orbital inclination. We discuss the properties of V523 Lyr and show that it is a member of the growing group of anomalous Z Cam type CVs, systems which show stunted outbursts, light curve standstills, and occasional deep drops in brightness.

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E. Mason, S. B. Howell. 2016-03-04. The Kepler and Hale observations of V523 Lyr. https://doi.org/10.1051/0004-6361/201628245

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