Outliers: multicolour photometry guiding the search for evolved binary systems in the globular cluster 47 Tucanae. Issue 4 (20th September 2018)

• Record Type: Journal Article
• Authors: Campos, Fabíola; Pelisoli, I; Kamann, S; Husser, T-O; Dreizler, S; Bellini, A; Robinson, E L; Nardiello, D; Piotto, G; Kepler, S O; Istrate, A G; Winget, D E; Montgomery, M H; Dotter, A
• Is Part Of: Monthly notices of the Royal Astronomical Society. Volume 481:Issue 4(2018)
• Page Start: 4397
• Page End: 4409
• Publication Date: 2018-09-20
• Subjects: binaries: general -- Hertzsprung–Russell and colour–magnitude diagrams -- white dwarfs -- globular clusters: individual: 47 Tuc; Astronomy -- Periodicals; Periodicals; 520.5
• DOI: 10.1093/mnras/sty2591
• Languages: English
• ISSNs: 0035-8711

Abstract

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.