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arXiv · 2504.12225

Narrowband Imaging of a z=3.24 Protocluster: Insights from [O III] Emitting Galaxies

Ke Shi·Jun Toshikawa·XianZhong Zheng·Zheng Cai·DongDong Shi
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Abstract

We present a narrowband imaging on a spectroscopically confirmed protocluster ``D4UD01'' at z=3.24 using CFHT/WIRCam. We identify a sample of 24 [O III] emission line galaxies in the field, which forms a large overdensity in the protocluster region. The protocluster is expected to evolve into a Virgo-like cluster by z=0. Utilizing multiwavelength data, we derive the physical properties of these [O III] emitters and find they are medium mass normal star-forming galaxies ($\sim10^{10}$M$_\odot$) roughly following the star-forming main sequence. The [O III] emitters trace an overdensity spatially offset from that of photometric-redshift and quiescent galaxies, suggesting these distinct galaxy populations may inhabit dark matter halos that formed at different epochs. A comparative analysis of [O III] emitter properties shows similar characteristics in both protocluster and field environments. This protocluster likely represents an evolved structure that has progressed beyond its peak star-formation phase, although our limited sample size may prevent detection of subtle environmental effects.

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Ke Shi, Jun Toshikawa, XianZhong Zheng, Zheng Cai, DongDong Shi. 2025-04-16. Narrowband Imaging of a z=3.24 Protocluster: Insights from [O III] Emitting Galaxies. https://arxiv.org/abs/2504.12225

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