Enrichment by Extragalactic First Stars in the Large Magellanic Cloud

• DOI: 10.48550/arxiv.2401.11307
• Publication Date: 2024-01-01
• Authors: Anirudh Chiti; Mohammad K. Mardini; Guilherme Limberg; Anna Frebel; Alexander P. Ji; Henrique Reggiani; P. S. Ferguson; Hillary Diane And...; Kaley Brauer; Ting S. Li; Joshua D. Simon
• Keywords: Large Magellanic Cloud

The Large Magellanic Cloud (LMC) is the Milky Way's most massive satellite galaxy, which only recently (~2 billion years ago) fell into our Galaxy. Since stellar atmospheres preserve their natal cloud's composition, LMC's recent infall makes its ancient, metal-deficient ("low-metallicity") stars unique windows early star formation and nucleosynthesis in a formerly distant region of high-redshift universe. Previously, identifying such LMC was challenging. But new techniques have opened this window, now enabling tests whether earliest element enrichment distant, extragalactic proto-galaxies deviated from what occurred proto-Milky Way. Here we present elemental abundances 10 with iron-to-hydrogen ratios ranging ~1/300th to ~1/12,000th Sun. Our 50 times more than any available detailed chemical abundance patterns, likely enriched by single first supernova. This lacks significant carbon-enhancement, as does overall sample, contrast lowest metallicity Way stars. This, other differences, affirm that experienced diverging processes compared Early production, driven stars, thus appears proceed an environment-dependent manner.