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EPIC 202843107 : A Close Eclipsing Binary Containing a {delta} Scuti Variable

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 نشر من قبل Ming Yang
 تاريخ النشر 2019
  مجال البحث فيزياء
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This paper reports on the discovery that an eclipsing binary system, EPIC 202843107 , has a {delta} Scuti variable component. The phased light curve from Kepler space telescope presents a detached configuration. The binary modelling indicates that the two component stars have almost the same radius and may have experienced orbital circularization. Frequency analyses are performed for the residual light curve after subtracting the binary variations. The frequency spectrum reveals that one component star is a {delta} Scuti variable. A large frequency separation is cross-identified with the histogram graph, the Fourier transform, and the echelle diagram method. The mean density of the {delta} Scuti component is estimated to be 0.09 g/cm3 based on the large separation and density relation. Systems like EPIC 202843107 are helpful to study the stellar evolution and physical state for binary stars.



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