2025/08/01 by Shihui Lin, S.J Lin, Baitian Tang +14 · 1 voice · 2 citations
Physics and Astronomy · #Abundance (ecology) #Astronomy and Astrophysical Research #Chemical evolution #Galactic halo #Galaxies: Formation, Evolution, Phenomena #Galaxy #Galaxy formation and evolution #Globular cluster #Milky Way #Stellar, planetary, and galactic studies #astro-ph.GA #astro-ph.SR
paper · pdf · doi:10.48550/arxiv.2508.00526
published in arXiv (Cornell University) (Cornell University)
openalex publication_date 2025/08/01 · arxiv published 2025/08/01 · arxiv updated 2025/08/15 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
Many Galactic globular clusters (GCs) originated in diverse host galaxies before being subsequently incorporated into the Milky Way through hierarchical galaxy assembly. Identifying their origins is crucial for revealing galaxy properties at early times. Traditional classification methods relying on dynamical properties face inherent uncertainties stemming from the evolving Galactic potential and complex merger histories. Chemically driven classification confronts a distinct obstacle: multiple populations - abundance variations in light elements of GC members. In this Letter, we identify primordial populations exhibiting lower [Al/Fe] as reliable tracers of their birth environments' chemical evolution. A clear chemical dichotomy emerges between in-situ and accreted GC populations at [Fe/H] > -1.5, particularly in the [Mg/Fe]-[Al/Fe] plane, indicating that their progenitor galaxies have experienced fundamentally different enrichment histories. While our chemically driven classification demonstrates general consistency with dynamically driven classifications, notable discrepancies emerge: NGC 288 and M4 are reclassified as in-situ, and Terzan 9 as accreted. This chemically driven GC classification provides promising application for Galactic archaeology.