_version_ 1866914089910927360
author Meyer, Romain A.
Wang, Feige
Kakiichi, Koki
Brammer, Gabe
Champagne, Jackie
Jurk, Katharina
Li, Zihao
Li, Zijian
Musin, Marat
Satyavolu, Sindhu
Schindler, Jan-Torge
Shuntov, Marko
Xu, Yi
Zou, Siwei
Bian, Fuyan
Casey, Caitlin
Egami, Eiichi
Fan, Xiaohui
Jiang, Danyang
Laporte, Nicolas
Liu, Weizhe
Oesch, Pascal
Tasca, Lidia
Yang, Jinyi
Zhang, Zijian
Akins, Hollis
Cai, Zheng
Coulter, Dave A.
Huang, Jiamu
Li, Mingyu
Liu, Weizhe
Liang, Yongming
Jin, Xiangyu
Kartaltepe, Jeyhan
Matharu, Jasleen
Pudoka, Maria
Tee, Wei-Leong
Witten, Callum
Zhang, Haowen
Zhu, Yongda
author_facet Meyer, Romain A.
Wang, Feige
Kakiichi, Koki
Brammer, Gabe
Champagne, Jackie
Jurk, Katharina
Li, Zihao
Li, Zijian
Musin, Marat
Satyavolu, Sindhu
Schindler, Jan-Torge
Shuntov, Marko
Xu, Yi
Zou, Siwei
Bian, Fuyan
Casey, Caitlin
Egami, Eiichi
Fan, Xiaohui
Jiang, Danyang
Laporte, Nicolas
Liu, Weizhe
Oesch, Pascal
Tasca, Lidia
Yang, Jinyi
Zhang, Zijian
Akins, Hollis
Cai, Zheng
Coulter, Dave A.
Huang, Jiamu
Li, Mingyu
Liu, Weizhe
Liang, Yongming
Jin, Xiangyu
Kartaltepe, Jeyhan
Matharu, Jasleen
Pudoka, Maria
Tee, Wei-Leong
Witten, Callum
Zhang, Haowen
Zhu, Yongda
contents We present a spectroscopically-selected [OIII]+Hb emitters catalogue at 6.75<z<9.05 and the resulting [OIII] 5008 ÅLuminosity Function (LF) in the COSMOS field. We leverage the 0.3 deg$^{2}$ covered to date by COSMOS-3D using NIRCam/WFSS F444W (90% of the survey) to perform the largest spectroscopic search for [OIII] emitters at 6.75<z<9.05. We present our catalogue of 237 [OIII] emitters and their associated completeness function. The inferred constraints on the [OIII] LF enable us to characterise the knee of the [OIII] LF, resulting in improved [OIII] LF constraints at z~7,8. Notably, we find evidence for an accelerated decline of the [OIII] luminosity density between z~7 and z~8, which could be expected if the metallicity of [OIII] emitters, as well as the cosmic star-formation rate density, is declining at these redshifts. We find that theoretical models that reproduce the z~7,8 [OIII] LF do not reproduce well the [OIII] equivalent width distribution, pointing to potential challenges in the modelling of[OIII] and other nebular lines in the early Universe. Finally, we provide the first constraints on the cosmic variance of [OIII] emitters, estimating at 15% the relative uncertainty for the z~7,8 [OIII] LF in the 0.3 deg$^2$ field. This estimate is in good agreement with that inferred from clustering, and shows that the [OIII] LF derived from smaller extragalactic legacy fields is strongly affected by cosmic variance. Our results highlight the fundamental role that wide-area JWST slitless surveys play to map the galaxy large-scale structure down into the reionisation era, serving as a springboard for a variety of science cases.
format Preprint
id arxiv_https___arxiv_org_abs_2510_11373
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle JWST COSMOS-3D: Spectroscopic Census and Luminosity Function of [O III] Emitters at 6.75<z<9.05 in COSMOS
Meyer, Romain A.
Wang, Feige
Kakiichi, Koki
Brammer, Gabe
Champagne, Jackie
Jurk, Katharina
Li, Zihao
Li, Zijian
Musin, Marat
Satyavolu, Sindhu
Schindler, Jan-Torge
Shuntov, Marko
Xu, Yi
Zou, Siwei
Bian, Fuyan
Casey, Caitlin
Egami, Eiichi
Fan, Xiaohui
Jiang, Danyang
Laporte, Nicolas
Liu, Weizhe
Oesch, Pascal
Tasca, Lidia
Yang, Jinyi
Zhang, Zijian
Akins, Hollis
Cai, Zheng
Coulter, Dave A.
Huang, Jiamu
Li, Mingyu
Liu, Weizhe
Liang, Yongming
Jin, Xiangyu
Kartaltepe, Jeyhan
Matharu, Jasleen
Pudoka, Maria
Tee, Wei-Leong
Witten, Callum
Zhang, Haowen
Zhu, Yongda
Astrophysics of Galaxies
We present a spectroscopically-selected [OIII]+Hb emitters catalogue at 6.75<z<9.05 and the resulting [OIII] 5008 ÅLuminosity Function (LF) in the COSMOS field. We leverage the 0.3 deg$^{2}$ covered to date by COSMOS-3D using NIRCam/WFSS F444W (90% of the survey) to perform the largest spectroscopic search for [OIII] emitters at 6.75<z<9.05. We present our catalogue of 237 [OIII] emitters and their associated completeness function. The inferred constraints on the [OIII] LF enable us to characterise the knee of the [OIII] LF, resulting in improved [OIII] LF constraints at z~7,8. Notably, we find evidence for an accelerated decline of the [OIII] luminosity density between z~7 and z~8, which could be expected if the metallicity of [OIII] emitters, as well as the cosmic star-formation rate density, is declining at these redshifts. We find that theoretical models that reproduce the z~7,8 [OIII] LF do not reproduce well the [OIII] equivalent width distribution, pointing to potential challenges in the modelling of[OIII] and other nebular lines in the early Universe. Finally, we provide the first constraints on the cosmic variance of [OIII] emitters, estimating at 15% the relative uncertainty for the z~7,8 [OIII] LF in the 0.3 deg$^2$ field. This estimate is in good agreement with that inferred from clustering, and shows that the [OIII] LF derived from smaller extragalactic legacy fields is strongly affected by cosmic variance. Our results highlight the fundamental role that wide-area JWST slitless surveys play to map the galaxy large-scale structure down into the reionisation era, serving as a springboard for a variety of science cases.
title JWST COSMOS-3D: Spectroscopic Census and Luminosity Function of [O III] Emitters at 6.75<z<9.05 in COSMOS
topic Astrophysics of Galaxies
url https://arxiv.org/abs/2510.11373