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Outliers: multicolour photometry guiding the search for evolved binary systems in the globular cluster 47 Tucanae

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 نشر من قبل Fabiola Campos
 تاريخ النشر 2018
  مجال البحث فيزياء
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We use Hubble Space Telescope multicolour photometry of the globular cluster 47 Tucanae to uncover a population of 24 objects with no previous classification that are outliers from the single-star model tracks in the colour-magnitude diagram and yet are likely cluster members. By comparing those sources with evolutionary models and X-ray source catalogues, we were able to show that the majority of those sources are likely binary systems that do not have any X-ray source detected nearby, most possibly formed by a white dwarf and a main-sequence star and a small number of possible double-degenerate systems.



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