Insights into Galaxy Morphology and Star Formation: Unveiling Filamentary Structures around an Extreme Overdensity at z ∼ 1.5 Traced by [O II] Emitters
Abstract
We explore the morphological features and star formation activities of [O II] emitters in the COSMOS UltraDeep field at z ∼ 1.5 using JWST NIRCam data from the COSMOS-Web survey and Subaru Hyper Suprime-Cam. We also report the discovery of large filamentary structures traced by [O II] emitters surrounding an extremely overdense core with a galaxy number density ∼11× higher than the field average. These structures span over 50 cMpc, underscoring their large scale in the cosmic web at this epoch. After matching the stellar-mass distributions, the core galaxies show a higher frequency of disturbances (50% ± 9%) than those in the outskirts (41% ± 9%) and the field (21% ± 5%), indicative of more frequent mergers and interactions in the innermost ≲1.'5 region. Additionally, we observe that specific star formation rates are elevated in denser environments. A Kolmogorov–Smirnov test comparing the distribution of specific star formation rates of core and field galaxies yields a p-value of 0.02, suggesting an enhancement of star formation activity driven by the dense environment. Our findings underscore the environmental impact on galaxy evolution during a pivotal cosmic epoch and set the stage for further investigation with the increasing larger data from upcoming surveys.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- April 2024
- DOI:
- 10.3847/2041-8213/ad3238
- arXiv:
- arXiv:2403.06369
- Bibcode:
- 2024ApJ...964L..33L
- Keywords:
-
- Galaxy evolution;
- Galaxy environments;
- Galaxy structure;
- Galaxy properties;
- 594;
- 2029;
- 622;
- 615;
- Astrophysics - Astrophysics of Galaxies
- E-Print:
- 13 pages, 4 figures