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Bright Southern Variable Stars in the bRing Survey

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 نشر من قبل Samuel Mellon
 تاريخ النشر 2019
  مجال البحث فيزياء
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Besides monitoring the bright star $beta$ Pic during the near transit event for its giant exoplanet, the $beta$ Pictoris b Ring (bRing) observatories at Siding Springs Observatory, Australia and Sutherland, South Africa have monitored the brightnesses of bright stars ($V$ $simeq$ 4--8 mag) centered on the south celestial pole ($delta$ $leq$ -30$^{circ}$) for approximately two years. Here we present a comprehensive study of the bRing time series photometry for bright southern stars monitored between 2017 June and 2019 January. Of the 16762 stars monitored by bRing, 353 of them were found to be variable. Of the variable stars, 80% had previously known variability and 20% were new variables. Each of the new variables was classified, including 3 new eclipsing binaries (HD 77669, HD 142049, HD 155781), 26 $delta$ Scutis, 4 slowly pulsating B stars, and others. This survey also reclassified four stars based on their period of pulsation, light curve, spectral classification, and color-magnitude information. The survey data were searched for new examples of transiting circumsecondary disk systems, but no candidates were found.



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