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arXiv · 2203.11533

The OmegaWhite Survey for Short Period Variable Stars VI. Open Clusters

R. Toma·G. Ramsay·C. S. Jeffery·S. A. Macfarlane·P. Woudt·P. J. Groot
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Abstract

Using light curves with $\sim$3 min cadence and a duration of 2 hrs made using the OmegaWhite survey, we present the results of a search for short-period variable stars in the field of 20 open clusters. We identified 92 variable stars in these fields. Using a range of cluster member catalogues and Gaia EDR3 data, we have determined that 10 are cluster members and 2 more are probable members. Based on their position on the Gaia HRD and their photometric periods, we find that most of these are $\delta$ Sct stars. We obtained low-resolution optical spectroscopy of some of these cluster members and field stars. We discuss the cluster variable stars in the context of $\delta$ Sct stars in other open clusters.

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R. Toma, G. Ramsay, C. S. Jeffery, S. A. Macfarlane, P. Woudt, P. J. Groot. 2022-03-22. The OmegaWhite Survey for Short Period Variable Stars VI. Open Clusters. https://doi.org/10.1093/mnras%2Fstac802

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