Chemical Abundances in the Metal-Poor Globular Cluster ESO 280-SC06: A Formerly Massive, Tidally Disrupted Globular Cluster
We present the first high-resolution abundance study of ESO 280-SC06, one of the least luminous and most metal-poor gravitationally bound Milky Way globular clusters. Using Magellan/MIKE spectroscopy for ten stars, we confirm the cluster's low metallicity as [Fe/H] = $-2.54 \pm 0.06$ and the pr...
Saved in:
| Main Authors: | , , , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Maynooth Academic Publishing
2025-07-01
|
| Series: | The Open Journal of Astrophysics |
| Online Access: | https://doi.org/10.33232/001c.141756 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| Summary: | We present the first high-resolution abundance study of ESO 280-SC06, one of the least luminous and most metal-poor gravitationally bound Milky Way globular clusters. Using Magellan/MIKE spectroscopy for ten stars, we confirm the cluster's low metallicity as [Fe/H] = $-2.54 \pm 0.06$ and the presence of a nitrogen-enhanced star enriched by binary mass transfer. We determine abundances or abundance upper limits for 21 additional elements from the light, alpha, odd-Z, iron peak, and neutron-capture groups for all ten stars. We find no spread in neutron-capture elements, unlike previous trends identified in some metal-poor globular clusters such as M15 and M92. Eight of the ten stars have light-element abundance patterns consistent with second-population globular cluster stars, which is a significantly larger second-population fraction than would be expected from the low present-day mass of $10^{4.1}$ Msun. We estimate the initial mass of the cluster as $10^{5.4 - 5.7}$ Msun based on its orbit in the Milky Way. A preferential loss of first-population stars could explain the high fraction of second-population stars at the present time. Our results emphasize the importance of considering mass loss when studying globular clusters and their enrichment patterns. |
|---|---|
| ISSN: | 2565-6120 |