Abstract
We report the discovery of a large-scale structure at z = 3.44 revealed by JWST data in the Extended Groth Strip (EGS) field. This structure, called the Cosmic Vine, consists of 20 galaxies with spectroscopic redshifts at 3.43 < z < 3.45 and six galaxy overdensities (4−7σ) with consistent photometric redshifts, making up a vine-like structure extending over a ∼4 × 0.2 pMpc2 area. The two most massive galaxies (M∗ ≈ 1010.9 M ) of the Cosmic Vine are found to be quiescent with bulge-dominated morphologies (B/T > 70%). Comparisons with simulations suggest that the Cosmic Vine would form a cluster with halo mass Mhalo > 1014M at z = 0, and the two massive galaxies are likely forming the brightest cluster galaxies (BCGs). The results unambiguously reveal that massive quiescent galaxies can form in growing large-scale structures at z > 3, thus disfavoring the environmental quenching mechanisms that require a virialized cluster core. Instead, as suggested by the interacting and bulge-dominated morphologies, the two galaxies are likely quenched by merger-triggered starburst or active galactic nucleus (AGN) feedback before falling into a cluster core. Moreover, we found that the observed specific star formation rates of massive quiescent galaxies in z > 3 dense environments are one to two orders of magnitude lower than that of the BCGs in the TNG300 simulation. This discrepancy potentially poses a challenge to the models of massive cluster galaxy formation. Future studies comparing a large sample with dedicated cluster simulations are required to solve the problem.
Originalsprog | Engelsk |
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Artikelnummer | L4 |
Tidsskrift | Astronomy & Astrophysics |
Vol/bind | 683 |
Antal sider | 10 |
ISSN | 0004-6361 |
DOI | |
Status | Udgivet - 29 feb. 2024 |
Bibliografisk note
Funding Information:SJ acknowledges the financial support from the European Union’s Horizon Europe research and innovation program under the Marie Skłodowska-Curie grant No. 101060888. The Cosmic Dawn Center (DAWN) is funded by the Danish National Research Foundation under grant DNRF140. GEM and SG acknowledge financial support from the Villum Young Investigator grant 37440 and 13160. APV and TRG acknowledges support from the Carlsberg Foundation (grant no CF20-0534). We acknowledge the CANDIDE cluster at the Institut d’Astrophysique de Paris, which was funded through grants from the PNCG, CNES, DIM-ACAV, and the Cosmic Dawn Center and maintained by Stephane Rouberol.
Publisher Copyright:
© The Authors 2024.