A Comprehensive JWST Slitless Spectroscopic Census of ∼12,000 Emission-Line Galaxies at Redshift 0∼9 in COSMOS
Abstract
Emission-line galaxies provide key diagnostics of star formation, chemical enrichment, and AGN activity across cosmic time. We present a systematic census of emission-line sources using JWST/NIRCam wide-field slitless spectroscopy (WFSS) from the COSMOS-3D program, which covers a large contiguous area of 0.33 deg2 and provides F444W grism spectroscopy over $3.9−−5.1\ μ$m. By combining slitless spectroscopy with deep multi-band imaging data, we construct a homogeneous spectroscopic sample of 12,275 objects at redshift 0--9. The typical 3σ line-flux limit reaches 3.2×10−18 erg s−1 cm−2. To address source confusion inherent to slitless spectroscopy, we develop a multi-step identification framework that combines information from spectra, images, spectral energy distributions, and spatial distributions. We introduce convolutional neural network and large language model to emulate the human identification process and improve efficiency. The resulting catalog provides spectroscopic redshifts, emission-line measurements, and derived physical properties for all sources. The F444W WFSS enables the detection of multiple emission lines, including primarily [O III], Hα, He I λ10830, [S III] λλ9531,9069, Paβ, Paα, Brβ, PAH, Brα, allowing a continuous census of galaxies across cosmic time. We construct composite spectra in several redshift bins and detect a variety of faint spectral features that are difficult to identify in individual spectra, including higher-order hydrogen recombination lines, CO absorption bands, and [Fe II] lines. This catalog provides a key reference dataset for studies of galaxy evolution and AGN activity, and demonstrates the power of WFSS for constructing large, unbiased spectroscopic samples over wide areas. The full catalog will be publicly available online upon publication.
Related
- Characterizing Lyman alpha emission from high-redshift galaxies
- Extreme MgII Emission in Recently-Quenched Galaxies: A New Sample of Intermediate-Redshift Post-Starburst Quasars from the DESI Early Data Release
- Precision kinematic Sunyaev-Zel’dovich measurements across halo mass and redshift with DESI DR2 and ACT DR6. II. Bright galaxy survey and emission-line galaxies
- geko : A tool for modelling galaxy kinematics and morphology in JWST /NIRCam slitless spectroscopic observations
- An Archival Calibration of JWST/MIRI Prism Wide-Field Slitless Spectroscopy: Methodology, Performance, and a Mid-Infrared Spectral Atlas of Galaxies at z=0−4 in the GOODS-N/S Fields
BibTeX
@misc{fu2026comprehensive,
title = {{A Comprehensive JWST Slitless Spectroscopic Census of $\sim$12,000 Emission-Line Galaxies at Redshift $0\sim9$ in COSMOS}},
author = {Shuqi Fu and Zijian Zhang and Danyang Jiang and Jie Chen and Linhua Jiang and Chenxi Bao and Yihe Wang and Ronaldo Laishram},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2610.13920},
eprint = {2610.13920},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2610.13920},
}
RIS
TY - UNPB
TI - A Comprehensive JWST Slitless Spectroscopic Census of ∼12,000 Emission-Line Galaxies at Redshift 0∼9 in COSMOS
AU - Shuqi Fu
AU - Zijian Zhang
AU - Danyang Jiang
AU - Jie Chen
AU - Linhua Jiang
AU - Chenxi Bao
AU - Yihe Wang
AU - Ronaldo Laishram
PY - 2026
DA - 2026/10/09
PB - arXiv
DO - 10.48550/arxiv.2610.13920
UR - https://arxiv.org/abs/2610.13920
AB - Emission-line galaxies provide key diagnostics of star formation, chemical enrichment, and AGN activity across cosmic time. We present a systematic census of emission-line sources using JWST/NIRCam wide-field slitless spectroscopy (WFSS) from the COSMOS-3D program, which covers a large contiguous area of 0.33 deg^2 and provides F444W grism spectroscopy over $3.9−−5.1\ μ$m. By combining slitless spectroscopy with deep multi-band imaging data, we construct a homogeneous spectroscopic sample of 12,275 objects at redshift 0--9. The typical 3σ line-flux limit reaches 3.2×10^−18 erg s^−1 cm^−2. To address source confusion inherent to slitless spectroscopy, we develop a multi-step identification framework that combines information from spectra, images, spectral energy distributions, and spatial distributions. We introduce convolutional neural network and large language model to emulate the human identification process and improve efficiency. The resulting catalog provides spectroscopic redshifts, emission-line measurements, and derived physical properties for all sources. The F444W WFSS enables the detection of multiple emission lines, including primarily [O III], Hα, He I λ10830, [S III] λλ9531,9069, Paβ, Paα, Brβ, PAH, Brα, allowing a continuous census of galaxies across cosmic time. We construct composite spectra in several redshift bins and detect a variety of faint spectral features that are difficult to identify in individual spectra, including higher-order hydrogen recombination lines, CO absorption bands, and [Fe II] lines. This catalog provides a key reference dataset for studies of galaxy evolution and AGN activity, and demonstrates the power of WFSS for constructing large, unbiased spectroscopic samples over wide areas. The full catalog will be publicly available online upon publication.
ER -