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arXiv · 2505.18262

Enhanced Merger Fractions in a Reionization-Era Protocluster

Lorraine C. Marcelin·Jaclyn B. Champagne·Feige Wang·Xiaohui Fan·Maria Pudoka·Wei Leong Tee·Yongda Zhu
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Abstract

Mergers play a critical role in galaxy evolution, but their relationship to their surrounding environments is unexplored at high redshift. We investigate the galaxy merger rate among 124 [OIII] emitters at $5.3 3\sigma$ enhancement of the merger fraction amongst all three overdense structures compared to the field. Eleven galaxies are classified as ``active mergers" satisfying both merger criteria, all of which occur within the overdensity samples. We conclude that environment affects the merger rates of galaxies at $z>6$, leading to increased specific star formation at the 4$\sigma$ level.

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Lorraine C. Marcelin, Jaclyn B. Champagne, Feige Wang, Xiaohui Fan, Maria Pudoka, Wei Leong Tee, Yongda Zhu. 2025-05-23. Enhanced Merger Fractions in a Reionization-Era Protocluster. https://arxiv.org/abs/2505.18262

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