The eventful life of a luminous galaxy at z = 14: Metal enrichment, feedback, and low gas fraction?
Journal article, 2025
JADES-GS-z14-0 is the most distant spectroscopically confirmed galaxy yet, at z & 14. With a UV magnitude of -20.81, it is one of the most luminous galaxies at cosmic dawn and its half-light radius of 260 pc means that stars dominate the observed UV emission. We report the Atacama Large Millimeter/submillimeter Array (ALMA) detection of [O iii]88 μm line emission with a significance of 6.67σ and at a frequency of 223.524 GHz, corresponding to a redshift of 14:1796±0:0007, which is consistent with the candidate Ciii] line detected in the NIRSpec spectrum. At this spectroscopic redshift, the Lyman-α break identified with NIRSpec requires a damped Lyman-α absorber with a column density of log(NHI=cm-2) = 21:96. The total [O iii]88 μm luminosity (log(L[OIII]=L⊙) = 8:3 ± 0:1) is fully consistent with the local L[OIII] - S FR relation and indicating a gas-phase metallicity >0:1 Z⊙. Using prospector spectral energy distribution (SED) modeling and combining the ALMA data with JWST observations, we find Z = 0:17 Z⊙ and a nonzero escape fraction of ionizing photons (∼11%), which is necessary by the code to reproduce the UV spectrum. We measure an [OIII]5007A=[OIII]88 μm line flux ratio between 1 and 20, resulting in an upper limit to the electron density of roughly 700 cm-3 assuming a single-cloud photoionization model. The [O iii]emission line is spectrally resolved, with a FWHM of 102+29 -22 km s-1, resulting in a dynamical mass of log(Mdyn=M⊙) = 9:0 ± 0:2. When compared to the stellar mass, this value represents a conservative upper limit on the gas mass fraction, which ranges from 50% to 80%, depending on the assumed star formation history. Past radiationdriven outflows may have cleared the galaxy from the gas, reducing the gas fraction and thus increasing the escape fraction of ionizing photons.
Galaxies: ISM
Galaxies: evolution
Galaxies: formation
Galaxies: high-redshift
Author
S. Carniani
Scuola Normale Superiore di Pisa
Francesco D'Eugenio
University of Cambridge
Istituto nazionale di astrofisica (INAF)
Xihan Ji
University of Cambridge
Eleonora Parlanti
Scuola Normale Superiore di Pisa
Jan Scholtz
University of Cambridge
Fengwu Sun
Harvard-Smithsonian Center for Astrophysics
Giacomo Venturi
Scuola Normale Superiore di Pisa
Tom Bakx
Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics
Mirko Curti
European Southern Observatory (ESO)
R. Maiolino
University of Cambridge
University College London (UCL)
Sandro Tacchella
University of Cambridge
J. A. Zavala
National Astronomical Observatory of Japan
Kevin Hainline
University of Arizona
Joris Witstok
University of Cambridge
Cosmic Dawn Center (DAWN)
Benjamin D. Johnson
Harvard-Smithsonian Center for Astrophysics
Stacey Alberts
University of Arizona
Andrew J. Bunker
University of Oxford
Stephane Charlot
Institut d 'Astrophysique de Paris
Daniel Eisenstein
Harvard-Smithsonian Center for Astrophysics
Jakob M. Helton
University of Arizona
Peter Jakobsen
Niels Bohr Institute
Cosmic Dawn Center (DAWN)
Nimisha Kumari
Space Telescope Science Institute (STScI)
Brant Robertson
University of California
A. Saxena
University College London (UCL)
University of Oxford
Hannah Übler
University of Cambridge
Christina C. Williams
NOIRLab
Christopher N.A. Willmer
University of Arizona
C. Willott
National Research Council Canada
Astronomy and Astrophysics
0004-6361 (ISSN) 1432-0746 (eISSN)
Vol. 696 A87Subject Categories (SSIF 2025)
Atom and Molecular Physics and Optics
Astronomy, Astrophysics, and Cosmology
DOI
10.1051/0004-6361/202452451