Terzan 5: a Fossil Remnant of the Galactic Bulge

TL;DR

Terzan 5 is a stellar system in the Galactic Bulge with multiple stellar populations and chemical patterns similar to bulge stars, indicating it is a remnant of the bulge rather than a typical globular cluster.

Contribution

The paper presents evidence that Terzan 5 is a fossil remnant of the Galactic bulge, based on its unique stellar populations and chemical properties.

Findings

Hosts two stellar populations with different iron abundances

Lacks anticorrelation typical of globular clusters

Chemically similar to Bulge stars

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 ({\Delta}[Fe/H]=0.5). Such a large difference has been measured only in {\omega} 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.