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arXiv · 1809.07746

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

Fabiola Campos·I. Pelisoli·S. Kamann·T. -O. Husser·S. Dreizler·A. Bellini·E. L. Robinson·D. Nardiello·G. Piotto·S. O. Kepler·A. G. Istrate·D. E. Winget·M. H. Montgomery·A. Dotter
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Abstract

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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Fabiola Campos, I. Pelisoli, S. Kamann, T. -O. Husser, S. Dreizler, A. Bellini, E. L. Robinson, D. Nardiello, G. Piotto, S. O. Kepler, A. G. Istrate, D. E. Winget, M. H. Montgomery, A. Dotter. 2018-09-20. Outliers: multicolour photometry guiding the search for evolved binary systems in the globular cluster 47 Tucanae. https://doi.org/10.1093/mnras%2Fsty2591

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