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arXiv · 1310.0537

Atypical Light Curves

Steven D. Steenwyk·Daniel M. Van Noord·Lawrence A. Molnar
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Abstract

We have identified some two-hundred new variable stars in a systematic study of a data archive obtained with the Calvin-Rehoboth observatory. Of these, we present five close binaries showing behaviors presumably due to star spots or other magnetic activity. For context, we first present two new RS CVn systems whose behavior can be readily attribute to star spots. Then we present three new close binary systems that are rather atypical, with light curves that are changing over time in ways not easily understood in terms of star spot activity generally associated with magnetically active binary systems called RS CVn systems. Two of these three are contact binaries that exhibit gradual changes in average brightness without noticeable changes in light curve shape. A third system has shown such large changes in light curve morphology that we speculate this may be a rare instance of a system that transitions back and forth between contact and noncontact configurations, perhaps driven by magnetic cycles in at least one member of the binary.

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Steven D. Steenwyk, Daniel M. Van Noord, Lawrence A. Molnar. 2013-10-02. Atypical Light Curves. https://arxiv.org/abs/1310.0537

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