Terzan 5: a pristine fragment of the Bulge. (5th March 2015)

• Record Type: Journal Article
• Authors: Ferraro, Francesco R.
• Editors: Montmerle, Thierry
• Is Part Of: Proceedings of the International Astronomical Union. Volume 10:Number H16(2012)Highlights
• Page Start: 243
• Page End: 244
• Publication Date: 2015-03-05
• Subjects: Stars: abundances, -- Globular clusters: individual (Terzan 5); Astronomy -- Congresses; Astronomy -- Periodicals; 520
• DOI: 10.1017/S1743921314005602
• Languages: English
• ISSNs: 1743-9213

Abstract

Abstract: We have discovered that Terzan 5, a stellar system in the Galactic Bulge, harbors two stellar populations with different iron content (Δ[Fe/H] ~ 0.5 dex) and possibly different ages. Moreover, the observed chemical patterns significantly differ from those observed in any known genuine globular cluster. These evidences demonstrate that, similarly to ω Centauri in the Halo, Terzan 5 is not a globular cluster, but a stellar system that was able to retain the gas ejected by violent supernova explosions. Moreover the striking chemical similarity with the Bulge stars suggests that Terzan 5 could be the relic of one of the massive clumps that contributed (through strong dynamical interactions with other pre-formed and internally-evolved sub-structures) to the formation of the Galactic Bulge.