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Deciphering the Surprising Variability of A-type Stars Revealed by Kepler

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 نشر من قبل James Sikora
 تاريخ النشر 2017
  مجال البحث فيزياء
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A recent analysis of high precision photometry obtained using the Kepler spacecraft has revealed two surprising discoveries: (1) over 860 main sequence A-type stars -- approximately 40% of those identified in the Kepler field -- exhibit periodic variability that may be attributable to rotational modulation by spots and (2) many of their light curves indicate the presence of a mysterious and characteristic power spectral feature. We have been carrying out an ongoing analysis designed to expand upon these discoveries and to provide a possible explanation for the unusual power spectral features. In the following, we will put these recent discoveries into context as well as discuss the preliminary findings yielded by our analysis of the Kepler light curves.

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