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arXiv · 1901.08574

Three candidate globular clusters discovered in the Galactic bulge

Denilso Camargo·Dante Minniti
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Abstract

This work reports the discovery of three new globular clusters (GCs) towards the Galactic bulge - Camargo 1107, 1108, and 1109. The discovery was made using the WISE, 2MASS, VVV, and Gaia-DR2 photometry. The new findings are old (12.0-13.5 Gyr) and metal-poor GCs ([Fe/H] < -1.5 dex) located in the bulge area close to the Milky Way (MW) mid-plane. Although the old ages and low metallicities suggest that the newly discovered GCs are likely associated with the inner halo the possibility of these clusters being part of a primordial bulge GC subpopulation cannot be ruled out. Camargo 1107, for instance, presents a metallicity of [Fe/H] = -2.2 +/- 0.4 dex and an age of 13.5 +/- 2 Gyr, which may suggest that this cluster formed just after the Big Bang in the very early Universe. The discovery of GCs such as the new findings is crucial to built a coherent picture of the inner Galaxy. It is likely that at least a few more dozens of GCs are still to be discovered in the bulge.

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Denilso Camargo, Dante Minniti. 2019-01-24. Three candidate globular clusters discovered in the Galactic bulge. https://doi.org/10.1093/mnrasl%2Fslz010

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