Discovery of a stellar system in the background of 47 Tucanae

Abstract

We report on the discovery of a stellar system in the background of the Galactic globular cluster 47 Tucanae (NGC 104), located 14.8' North-West of the cluster center. The object, whose apparent diameter is D~30'', is partially resolved into stars on the available CCD images, reaching a limiting magnitude of V~22.5, and is detected as a significant (more than 5 sigma) overdensity of blue stars (B-V<0.7). The color magnitude diagram of the system, its characteristic projected size and its position in the sky suggest that it is an intermediate-old age cluster belonging to the Small Magellanic Cloud, whose outskirts lie in the background of 47 Tuc. Although less likely, the possibility that the object is an unknown dwarf galaxy in the outskirts of the Local Group cannot completely be ruled out by the present data.

5 pages, 5 figures, accepted for publication in A&A

References in corpus (5)

• New infrared star clusters in the southern Milky Way with 2MASS
• New infrared star clusters in the Northern and Equatorial Milky Way with 2MASS
• The calibration of the RGB Tip as a Standard Candle: Extension to Near Infrared colors and higher metallicity
• Discovery of another peculiar radial distribution of Blue Stragglers in Globular Clusters: The case of 47 Tuc
• The Southern Dwarf Hunt: Local Group Dwarf Candidates in the Southern Sky

Cited by in corpus (4)

• A general catalogue of extended objects in the Magellanic System
• Homogeneous photometry VII. Globular clusters in the Gaia era
• The Gradients in the 47 Tuc Red Giant Branch Bump and Horizontal Branch are Consistent With a Centrally-Concentrated, Helium-Enriched Second Stellar Generation
• Hierarchical structures in the Large and Small Magellanic Clouds