Ionizing Photon Production Efficiencies and Chemical Abundances at Cosmic Dawn Revealed by Ultradeep Rest-frame Optical Spectroscopy of JADES-GS-z14-0
21 affiliations
- 1The Pennsylvania State University
- 2University of Arizona
- 3University of Cambridge
- 4Space Telescope Science Institute
- 5Scuola Normale Superiore
- 6Northwestern University
- 7Center for Astrophysics ∣ Harvard and Smithsonian
- 8University of Copenhagen
- 9University of Oxford
- 10Sorbonne Université
- 11European Southern Observatory
- 12University of Hertfordshire
- 13Cosmic Dawn Center (DAWN)
- 14Tsinghua University
- 15University College London
- 16University of Wisconsin-Madison
- 17Centro de Astrobiología (CAB)
- 18University of California
- 19Max-Planck-Institut für extraterrestrische Physik (MPE)
- 20NSF National Optical-Infrared Astronomy Research Laboratory
- 21NRC Herzberg
Abstract
JWST has discovered an early period of galaxy formation that was more vigorous than expected, which has challenged our understanding of the early Universe. In this work, we present the longest spectroscopic integration ever acquired by JWST/MIRI ( t obs ≈ 51 hr). This spectrum covers the brightest rest-frame optical nebular emission lines for the luminous galaxy JADES-GS-z14-0 at z = 14.18. Most notably, we detect [O III ] λλ 4959, 5007 at ≈14 σ and H α at ≈4 σ with these ultradeep observations. These lines reveal that JADES-GS-z14-0 has low dust attenuation with a recent star formation rate of SFR ≈ 8 ± 2 M ⊙ yr −1 , star formation rate surface density of Σ SFR ≈ 20 ± 5 M ⊙ yr −1 kpc −2 , and ionizing photon production efficiency of ξ ion ≈ 10 25.3±0.1 Hz erg −1 . Using standard strong-line diagnostics, we infer a gas-phase oxygen abundance of log 10 ( O / H ) + 12 ≈ 7.5 ± 0.2 (≈6% Z ⊙ ), carbon-to-oxygen ratio of [C/O] ≈ −0.4 ± 0.2, ionization parameter of log 10 ( U ) ≳ − 2.4 , and density of n H ≈ 690 ± 200 cm −3 . Using detailed photoionization modeling, we instead derive log 10 ( O / H ) + 12 ≈ 8 . 5 − 0.4 + 0.4 (≈60% Z ⊙ ), log 10 ( U ) ≈ − 1 . 4 − 0.4 + 0.3 , and n H ≈ 54 0 − 320 + 520 cm − 3 . The inferred properties of JADES-GS-z14-0 are similar to those measured for similarly luminous galaxies at z > 10 with previous MIRI/Spectroscopy, such as GHZ2/GLASSz12, GN-z11, and MACS0647-JD1. These results suggest extreme ionization conditions and rapid metal enrichment less than 300 Myr after the Big Bang. Existing simulations are unable to reproduce the empirical and inferred properties of JADES-GS-z14-0. This work demonstrates an important step toward understanding the formation of the first stars and heavy elements in the Universe. Future work will focus on the detection of the rest-frame optical continuum and its interpretation for the stellar population properties of JADES-GS-z14-0.
Related
- Precise C-N-O Abundances of Individual Galaxies in the First Billion Years from Ultra-Deep, Rest-UV-to-Optical JWST Spectroscopy
- The Composition of M-dwarf Exoplanet Hosts: Atmospheric Parameters and O, Mg, Si, and Fe Abundances from IR Spectroscopy
- Probing the Assembly of Triangulum: Precision Metallicities and α Abundances of M33's Star Clusters from APOGEE Integrated-Light Spectroscopy
- Chemical abundance patterns at z=1-7: Carbon, Nitrogen, Neon, Sulphur, and Argon abundances from JWST spectroscopy
- Spectra and Ionization Efficiencies of Charged Decay Particles in Kilonova Ejecta
BibTeX
@article{helton2026ionizing,
title = {{Ionizing Photon Production Efficiencies and Chemical Abundances at Cosmic Dawn Revealed by Ultradeep Rest-frame Optical Spectroscopy of JADES-GS-z14-0}},
author = {Jakob M. Helton and Jane E. Morrison and Kevin Hainline and Francesco D’Eugenio and George H. Rieke and Stacey L. Alberts and Stefano Carniani and Joel Leja and Yijia Li and Pierluigi Rinaldi and Jan Scholtz and Meredith A. Stone and Christopher N. A. Willmer and Zihao Wu and William M. Baker and Andrew J. Bunker and S. Charlot and Jacopo Chevallard and Nikko J. Cleri and Mirko Curti and Emma Curtis-Lake and Eiichi Egami and Daniel J. Eisenstein and P. Jakobsen and Zhiyuan Ji and Benjamin D. Johnson and Nimisha Kumari and Xiaojing Lin and Jianwei Lyu and R. Maiolino and Michael V. Maseda and Pablo G. Pérez‐González and Marcia J. Rieke and Brant E. Robertson and Aayush Saxena and Fengwu Sun and Sandro Tacchella and Hannah Übler and Giacomo Venturi and Christina C. Williams and Chris J. Willott and Joris Witstok and Yongda Zhu},
journal = {The Astrophysical Journal Letters},
year = {2026},
month = jun,
doi = {10.3847/2041-8213/ae7446},
url = {https://hal.science/hal-05760819v1},
note = {CC BY-NC-ND 4.0},
}
RIS
TY - JOUR
TI - Ionizing Photon Production Efficiencies and Chemical Abundances at Cosmic Dawn Revealed by Ultradeep Rest-frame Optical Spectroscopy of JADES-GS-z14-0
AU - Jakob M. Helton
AU - Jane E. Morrison
AU - Kevin Hainline
AU - Francesco D’Eugenio
AU - George H. Rieke
AU - Stacey L. Alberts
AU - Stefano Carniani
AU - Joel Leja
AU - Yijia Li
AU - Pierluigi Rinaldi
AU - Jan Scholtz
AU - Meredith A. Stone
AU - Christopher N. A. Willmer
AU - Zihao Wu
AU - William M. Baker
AU - Andrew J. Bunker
AU - S. Charlot
AU - Jacopo Chevallard
AU - Nikko J. Cleri
AU - Mirko Curti
AU - Emma Curtis-Lake
AU - Eiichi Egami
AU - Daniel J. Eisenstein
AU - P. Jakobsen
AU - Zhiyuan Ji
AU - Benjamin D. Johnson
AU - Nimisha Kumari
AU - Xiaojing Lin
AU - Jianwei Lyu
AU - R. Maiolino
AU - Michael V. Maseda
AU - Pablo G. Pérez‐González
AU - Marcia J. Rieke
AU - Brant E. Robertson
AU - Aayush Saxena
AU - Fengwu Sun
AU - Sandro Tacchella
AU - Hannah Übler
AU - Giacomo Venturi
AU - Christina C. Williams
AU - Chris J. Willott
AU - Joris Witstok
AU - Yongda Zhu
PY - 2026
DA - 2026/06/15
JO - The Astrophysical Journal Letters
DO - 10.3847/2041-8213/ae7446
UR - https://hal.science/hal-05760819v1
AB - JWST has discovered an early period of galaxy formation that was more vigorous than expected, which has challenged our understanding of the early Universe. In this work, we present the longest spectroscopic integration ever acquired by JWST/MIRI ( t obs ≈ 51 hr). This spectrum covers the brightest rest-frame optical nebular emission lines for the luminous galaxy JADES-GS-z14-0 at z = 14.18. Most notably, we detect [O III ] λλ 4959, 5007 at ≈14 σ and H α at ≈4 σ with these ultradeep observations. These lines reveal that JADES-GS-z14-0 has low dust attenuation with a recent star formation rate of SFR ≈ 8 ± 2 M ⊙ yr −1 , star formation rate surface density of Σ SFR ≈ 20 ± 5 M ⊙ yr −1 kpc −2 , and ionizing photon production efficiency of ξ ion ≈ 10 25.3±0.1 Hz erg −1 . Using standard strong-line diagnostics, we infer a gas-phase oxygen abundance of log 10 ( O / H ) + 12 ≈ 7.5 ± 0.2 (≈6% Z ⊙ ), carbon-to-oxygen ratio of [C/O] ≈ −0.4 ± 0.2, ionization parameter of log 10 ( U ) ≳ − 2.4 , and density of n H ≈ 690 ± 200 cm −3 . Using detailed photoionization modeling, we instead derive log 10 ( O / H ) + 12 ≈ 8 . 5 − 0.4 + 0.4 (≈60% Z ⊙ ), log 10 ( U ) ≈ − 1 . 4 − 0.4 + 0.3 , and n H ≈ 54 0 − 320 + 520 cm − 3 . The inferred properties of JADES-GS-z14-0 are similar to those measured for similarly luminous galaxies at z > 10 with previous MIRI/Spectroscopy, such as GHZ2/GLASSz12, GN-z11, and MACS0647-JD1. These results suggest extreme ionization conditions and rapid metal enrichment less than 300 Myr after the Big Bang. Existing simulations are unable to reproduce the empirical and inferred properties of JADES-GS-z14-0. This work demonstrates an important step toward understanding the formation of the first stars and heavy elements in the Universe. Future work will focus on the detection of the rest-frame optical continuum and its interpretation for the stellar population properties of JADES-GS-z14-0.
SN - 2041-8205
SN - 2041-8213
ER -