Hint of bimodal Mg-Al anticorrelation in the metal-poor Globular Cluster NGC 4372
Abstract
We present a detailed chemical abundance analysis of seven red giant branch stars in the very metal-poor globular cluster NGC~4372, based on high-resolution UVES spectra. Our study aims to characterize the chemical evolution of NGC~4372 and investigate the presence of multiple populations. We derived abundances for 17 elements, including light, iron-peak, α, and heavy elements, using both equivalent width and spectral synthesis methods. We find a mean cluster metallicity of [Fe/H]=−2.36 ± 0.03 dex, with no evidence of an intrinsic iron spread. The cluster exhibits a typical α-enhancement of [α/Fe]= 0.33 ± 0.05 dex and a well defined Na-O anticorrelation, confirming that NGC 4372 hosts at least two distinct stellar populations. Furthermore, the measured ratio of [Ba/Eu] =−0.47 ± 0.04 indicates that the synthesis of heavy elements was dominated by r-process, consistent with other very metal-poor environments. We also identify a potential bimodal Mg-Al anticorrelation, which aligns with the patterns observed in GCs of similar mass and metallicity. These results reinforce the status of NGC 4372 as a cornerstone for understanding the early chemical enrichment of the Galactic Halo.
Related
- Hint of a bimodal Mg–Al anticorrelation in the metal-poor globular cluster NGC 4372
- Integrated Mass Loss for Very Metal-poor Stars: Asterosesimic Red Giant Masses of K2 Globular Cluster NGC 5897
- Ballistic mixing: Stellar mergers drive internal mixing in extremely massive stars with implications for proto-globular cluster pollution
- Globular cluster Observations for Luminosity-dispersion Distances (GOLD): Project description and velocity catalogue
- Reconstructing the Globular Cluster Initial Mass Function from Present-day Globular Cluster Systems
BibTeX
@misc{beltrand2026hint,
title = {{Hint of bimodal Mg-Al anticorrelation in the metal-poor Globular Cluster NGC 4372}},
author = {Camila Beltrand and Macarena Uribe and Sandro Villanova and César Muñoz},
howpublished = {arXiv},
year = {2026},
month = sep,
doi = {10.48550/arxiv.2609.04361},
eprint = {2609.04361},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2609.04361},
}
RIS
TY - UNPB
TI - Hint of bimodal Mg-Al anticorrelation in the metal-poor Globular Cluster NGC 4372
AU - Camila Beltrand
AU - Macarena Uribe
AU - Sandro Villanova
AU - César Muñoz
PY - 2026
DA - 2026/09/03
PB - arXiv
DO - 10.48550/arxiv.2609.04361
UR - https://arxiv.org/abs/2609.04361
AB - We present a detailed chemical abundance analysis of seven red giant branch stars in the very metal-poor globular cluster NGC~4372, based on high-resolution UVES spectra. Our study aims to characterize the chemical evolution of NGC~4372 and investigate the presence of multiple populations. We derived abundances for 17 elements, including light, iron-peak, α, and heavy elements, using both equivalent width and spectral synthesis methods. We find a mean cluster metallicity of [Fe/H]=−2.36 ± 0.03 dex, with no evidence of an intrinsic iron spread. The cluster exhibits a typical α-enhancement of [α/Fe]= 0.33 ± 0.05 dex and a well defined Na-O anticorrelation, confirming that NGC 4372 hosts at least two distinct stellar populations. Furthermore, the measured ratio of [Ba/Eu] =−0.47 ± 0.04 indicates that the synthesis of heavy elements was dominated by r-process, consistent with other very metal-poor environments. We also identify a potential bimodal Mg-Al anticorrelation, which aligns with the patterns observed in GCs of similar mass and metallicity. These results reinforce the status of NGC 4372 as a cornerstone for understanding the early chemical enrichment of the Galactic Halo.
ER -