_version_ 1866909982338842624
author Zhang, Yechi
Morishita, Takahiro
Kreilgaard, Kimi C.
Mason, Charlotte A.
Abdurro'uf
Atek, Hakim
Bradac, Marusa
Bradley, Larry D.
Bunker, Andrew J.
Gelli, Viola
Haryana, Novan Saputra
Hayes, Matthew J.
Helou, George
Leethochawalit, Nicha
Liu, Zhaoran
Rafelski, Marc
Roberts-Borsani, Guido
Rutkowski, Michael
Scarlata, Claudia
Stiavelli, Massimo
Sutanto, Ryo A.
Teplitz, Harry
Treu, Tommaso
Trenti, Michele
Vulcani, Benedetta
Wang, Xin
author_facet Zhang, Yechi
Morishita, Takahiro
Kreilgaard, Kimi C.
Mason, Charlotte A.
Abdurro'uf
Atek, Hakim
Bradac, Marusa
Bradley, Larry D.
Bunker, Andrew J.
Gelli, Viola
Haryana, Novan Saputra
Hayes, Matthew J.
Helou, George
Leethochawalit, Nicha
Liu, Zhaoran
Rafelski, Marc
Roberts-Borsani, Guido
Rutkowski, Michael
Scarlata, Claudia
Stiavelli, Massimo
Sutanto, Ryo A.
Teplitz, Harry
Treu, Tommaso
Trenti, Michele
Vulcani, Benedetta
Wang, Xin
contents We present photometric properties of 161 galaxy candidates at $z=7-14$ selected from the second data release (DR2) of BEACON, a JWST Cycle 2 pure-parallel NIRCam imaging program. Carefully selected from 36 independent pointings (corresponding to $\sim350$\,arcmin$^2$ sky coverage), and hence with reduced cosmic variance, our galaxy candidates provide an unbiased sample for investigating galaxy properties over a wide range of environments. We measure the physical properties, including UV continuum slope ($β_{\rm UV}$), stellar mass ($M_*$), star formation rate (SFR), and sizes. Our highest redshift galaxy candidate at $z=13.71\pm0.15$ has a remarkably bright UV luminosity of $M_{\rm UV}=-21.19\pm0.08$, making it the brightest galaxy at $z>12$ if spectroscopically confirmed. With an extremely blue UV slope, compact morphology, and high star formation rate surface density ($Σ_{\rm SFR}$), this candidate may have extremely low metallicity, high ionizing photon escape fraction, or contributions from an AGN. Among our multiple independent sightlines, we identify three fields of galaxy number overdensity with $>3σ$ significance. The properties of galaxies in various environments do not exhibit significant differences, implying either that accelerated galaxy evolution in overdense regions is not yet widespread at $z>7$, or that the current constraints are limited by sample size. Our simulations indicate that increasing the sample by an order of magnitude would allow such environmental trends to be robustly confirmed or ruled out, underscoring the importance of future pure-parallel observations.
format Preprint
id arxiv_https___arxiv_org_abs_2601_02861
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle BEACON: JWST NIRCam Pure-parallel Imaging Survey. II. Physical Properties of $z=7-14$ Galaxies
Zhang, Yechi
Morishita, Takahiro
Kreilgaard, Kimi C.
Mason, Charlotte A.
Abdurro'uf
Atek, Hakim
Bradac, Marusa
Bradley, Larry D.
Bunker, Andrew J.
Gelli, Viola
Haryana, Novan Saputra
Hayes, Matthew J.
Helou, George
Leethochawalit, Nicha
Liu, Zhaoran
Rafelski, Marc
Roberts-Borsani, Guido
Rutkowski, Michael
Scarlata, Claudia
Stiavelli, Massimo
Sutanto, Ryo A.
Teplitz, Harry
Treu, Tommaso
Trenti, Michele
Vulcani, Benedetta
Wang, Xin
Astrophysics of Galaxies
We present photometric properties of 161 galaxy candidates at $z=7-14$ selected from the second data release (DR2) of BEACON, a JWST Cycle 2 pure-parallel NIRCam imaging program. Carefully selected from 36 independent pointings (corresponding to $\sim350$\,arcmin$^2$ sky coverage), and hence with reduced cosmic variance, our galaxy candidates provide an unbiased sample for investigating galaxy properties over a wide range of environments. We measure the physical properties, including UV continuum slope ($β_{\rm UV}$), stellar mass ($M_*$), star formation rate (SFR), and sizes. Our highest redshift galaxy candidate at $z=13.71\pm0.15$ has a remarkably bright UV luminosity of $M_{\rm UV}=-21.19\pm0.08$, making it the brightest galaxy at $z>12$ if spectroscopically confirmed. With an extremely blue UV slope, compact morphology, and high star formation rate surface density ($Σ_{\rm SFR}$), this candidate may have extremely low metallicity, high ionizing photon escape fraction, or contributions from an AGN. Among our multiple independent sightlines, we identify three fields of galaxy number overdensity with $>3σ$ significance. The properties of galaxies in various environments do not exhibit significant differences, implying either that accelerated galaxy evolution in overdense regions is not yet widespread at $z>7$, or that the current constraints are limited by sample size. Our simulations indicate that increasing the sample by an order of magnitude would allow such environmental trends to be robustly confirmed or ruled out, underscoring the importance of future pure-parallel observations.
title BEACON: JWST NIRCam Pure-parallel Imaging Survey. II. Physical Properties of $z=7-14$ Galaxies
topic Astrophysics of Galaxies
url https://arxiv.org/abs/2601.02861