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arXiv · 1301.2436

Terzan 5: a Fossil Remnant of the Galactic Bulge

D. Massari·F. R. Ferraro·E. Dalessandro·B. Lanzoni·A. Mucciarelli·L. Origlia
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Abstract

Terzan 5 is a stellar system located in the Galactic Bulge, at a distance of 5.9 kpc. Recent discoveries show that it hosts two stellar populations with different iron abundance (Δ[Fe/H]=0.5). Such a large difference has been measured only in ω Centauri in the Galactic halo. Moreover no anticorrelation is observed in Terzan 5, hence it is not a genuine globular cluster. The observed chemical patterns are strikingly similar to those observed in the Bulge stars. This suggests that Terzan 5 is a remnant fragment of the Galactic bulge.

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D. Massari, F. R. Ferraro, E. Dalessandro, B. Lanzoni, A. Mucciarelli, L. Origlia. 2013-01-11. Terzan 5: a Fossil Remnant of the Galactic Bulge. https://arxiv.org/abs/1301.2436

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