BEACON: JWST NIRCam Pure-parallel Imaging Survey. IV. A Systematic Search for Galaxy Overdensities and Evidence for Gas Accretion Mode Transition

Ryo Albert Sutanto; Takahiro Morishita; Tadayuki Kodama; Abdurro'uf; Larry D. Bradley; Andrew J. Bunker; Nima Chartab; Nuo Chen; Matthew J. Hayes; George Helou; Novan Saputra Haryana; Nicha Leethochawalit; Zhaoran Liu; Charlotte A. Mason; Marc Rafelski; Michael J. Rutkowski; Massimo Stiavelli; Kosuke Takahashi; Harry I. Teplitz; Michele Trenti; Tommaso Treu; Benedetta Vulcani; Yechi Zhang

arXiv · 2602.04333

BEACON: JWST NIRCam Pure-parallel Imaging Survey. IV. A Systematic Search for Galaxy Overdensities and Evidence for Gas Accretion Mode Transition

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Abstract

We systematically search for galaxy overdensities using 20 independent fields with a minimum of six filters (F090W, F115W, F150W, F277W, F356W, and F444W) from BEACON, the JWST Cycle 2 NIRCam pure-parallel imaging survey. We apply an adaptive kernel-density estimation method that incorporates the full photometric redshift probability distribution function of each galaxy to map galaxy overdensities, and identify 207 significant ($>4\,\sigma$) overdensities at $1.5 3$, potentially due to a larger cold gas supply in earlier times. Our study reveals a complex interplay between individual galaxies and large-scale environmental properties, marking the onset of environmental effects on galaxy quenching in massive halos at cosmic noon.

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Ryo Albert Sutanto, Takahiro Morishita, Tadayuki Kodama, Abdurro'uf, Larry D. Bradley, Andrew J. Bunker, Nima Chartab, Nuo Chen, Matthew J. Hayes, George Helou, Novan Saputra Haryana, Nicha Leethochawalit, Zhaoran Liu, Charlotte A. Mason, Marc Rafelski, Michael J. Rutkowski, Massimo Stiavelli, Kosuke Takahashi, Harry I. Teplitz, Michele Trenti, Tommaso Treu, Benedetta Vulcani, Yechi Zhang. 2026-02-04. BEACON: JWST NIRCam Pure-parallel Imaging Survey. IV. A Systematic Search for Galaxy Overdensities and Evidence for Gas Accretion Mode Transition. https://arxiv.org/abs/2602.04333

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