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arXiv · 2509.14613

Chemical Enrichment of Isolated Relic Galaxy Mrk1216

M. Kıyami Erdim·Emine Gülmez·Murat Hüdaverdi
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Abstract

In this study, we investigate the chemical enrichment and structural evolution of the isolated elliptical relic galaxy Mrk1216 through X-ray observations. As a red-nugget relic, Mrk1216 provides a rare window into the early Universe, owing to its minimal interaction with the surrounding environment. Using data from the XMM-Newton telescope, we model the X-ray emission of its interstellar medium to derive radial temperature and abundance profiles. We find that the central region exhibits an elevated [Mg/Fe] ratio compared to typical early-type galaxies, consistent with a brief but intense star formation episode during its early assembly-a hallmark of relic systems. The nearly flat SNIa ratio profile ($R_{Ia} \sim 0.17$) extending to $\sim0.42R_{500}$ supports an early-enrichment scenario. These results highlight the importance of relic galaxies as benchmarks for studying early galaxy evolution and chemical enrichment. Future high-resolution missions and more advanced theoretical models incorporating more realistic initial mass functions are needed to fully assess their implications.

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M. Kıyami Erdim, Emine Gülmez, Murat Hüdaverdi. 2025-09-18. Chemical Enrichment of Isolated Relic Galaxy Mrk1216. https://doi.org/10.1017/pasa.2025.10098

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