Metal-Poor Gas Accretion Drives Giant Clump Formation at 0.6 < z < 2.6

Visal Sok; Adam Muzzin; Ben Forrest; Gillian Wilson; Jialu Chen; Vivian Yun Yan Tan; Sunna Withers; Roberto Abraham; Maruša Bradač; Vicente Estrada-Carpenter; Kartheik G. Iyer; Nicholas S. Martis; Gaël Noirot; Ghassan T. E. Sarrouh; Marcin Sawicki; Chris J. Willott; Aurélien Henry; Naadiyah Jagga; Danilo Marchesini; Ian McConachie; Katherine Myers; Nelson Nunes; Luke Robbins

arXiv · 2606.05284

Metal-Poor Gas Accretion Drives Giant Clump Formation at 0.6 < z < 2.6

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Abstract

The physical properties of kiloparsec-scale clumps in high-redshift star-forming galaxies (SFGs) contain crucial constraints on how they assemble. Building on recent work that indicates the presence of a metallicity offset in clumpy galaxies compared to nonclumpy SFGs, we analyze the chemical abundance in a large sample of ${\sim}300$ SFGs between $0.6 0$. We do not find a significant mass difference between these two clump populations. Finally, we compute the merger statistic using the Gini-M20 morphological parameters and find that the majority of clumpy galaxies are not classified as mergers based on their stellar mass maps. The results suggest that the clumpy nature of cosmic noon galaxies is linked to metal-poor gas accretion events that trigger star formation and dilute metallicities.

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Visal Sok, Adam Muzzin, Ben Forrest, Gillian Wilson, Jialu Chen, Vivian Yun Yan Tan, Sunna Withers, Roberto Abraham, Maruša Bradač, Vicente Estrada-Carpenter, Kartheik G. Iyer, Nicholas S. Martis, Gaël Noirot, Ghassan T. E. Sarrouh, Marcin Sawicki, Chris J. Willott, Aurélien Henry, Naadiyah Jagga, Danilo Marchesini, Ian McConachie, Katherine Myers, Nelson Nunes, Luke Robbins. 2026-06-03. Metal-Poor Gas Accretion Drives Giant Clump Formation at 0.6 < z < 2.6. https://arxiv.org/abs/2606.05284

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