The Astrophysical Journal Letters (Jan 2023)
The Gas and Stellar Content of a Metal-poor Galaxy at z = 8.496 as Revealed by JWST and ALMA
- K. E. Heintz,
- C. Giménez-Arteaga,
- S. Fujimoto,
- G. Brammer,
- D. Espada,
- S. Gillman,
- J. González-López,
- T. R. Greve,
- Y. Harikane,
- B. Hatsukade,
- K. K. Knudsen,
- A. M. Koekemoer,
- K. Kohno,
- V. Kokorev,
- M. M. Lee,
- G. E. Magdis,
- E. J. Nelson,
- F. Rizzo,
- R. L. Sanders,
- D. Schaerer,
- A. E. Shapley,
- V. B. Strait,
- S. Toft,
- F. Valentino,
- A. van der Wel,
- A. P. Vijayan,
- D. Watson,
- F. E. Bauer,
- C. R. Christiansen,
- S. N. Wilson
Affiliations
- K. E. Heintz
- ORCiD
- Cosmic Dawn Center (DAWN) , Denmark ; [email protected]; Niels Bohr Institute, University of Copenhagen , Jagtvej 128, DK-2200 Copenhagen N, Denmark
- C. Giménez-Arteaga
- ORCiD
- Cosmic Dawn Center (DAWN) , Denmark ; [email protected]; Niels Bohr Institute, University of Copenhagen , Jagtvej 128, DK-2200 Copenhagen N, Denmark
- S. Fujimoto
- ORCiD
- Cosmic Dawn Center (DAWN) , Denmark ; [email protected]; Niels Bohr Institute, University of Copenhagen , Jagtvej 128, DK-2200 Copenhagen N, Denmark; Department of Astronomy, The University of Texas at Austin , Austin, TX 78712, USA
- G. Brammer
- ORCiD
- Cosmic Dawn Center (DAWN) , Denmark ; [email protected]; Niels Bohr Institute, University of Copenhagen , Jagtvej 128, DK-2200 Copenhagen N, Denmark
- D. Espada
- ORCiD
- Departamento de Física Teórica y del Cosmos, Campus de Fuentenueva, Edificio Mecenas, Universidad de Granada , E-18071, Granada, Spain; Instituto Carlos I de Física Teórica y Computacional , Facultad de Ciencias, E-18071, Granada, Spain
- S. Gillman
- ORCiD
- Cosmic Dawn Center (DAWN) , Denmark ; [email protected]; DTU-Space, Technical University of Denmark , Elektrovej 327, DK-2800, Kgs. Lyngby, Denmark
- J. González-López
- ORCiD
- Las Campanas Observatory, Carnegie Institution of Washington , Casilla 601, La Serena, Chile; Núcleo de Astronomía, Facultad de Ingeniería y Ciencias, Universidad Diego Portales , Av. Ejército Libertador 441, Santiago, Chile
- T. R. Greve
- ORCiD
- Cosmic Dawn Center (DAWN) , Denmark ; [email protected]; DTU-Space, Technical University of Denmark , Elektrovej 327, DK-2800, Kgs. Lyngby, Denmark
- Y. Harikane
- ORCiD
- Institute for Cosmic Ray Research, The University of Tokyo , 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8582, Japan
- B. Hatsukade
- ORCiD
- Institute of Astronomy, Graduate School of Science, The University of Tokyo , 2-21-1 Osawa, Mitaka, Tokyo 181-0015, Japan
- K. K. Knudsen
- ORCiD
- Department of Space, Earth and Environment, Chalmers University of Technology , Onsala Space Observatory, SE-439 92 Onsala, Sweden
- A. M. Koekemoer
- ORCiD
- Space Telescope Science Institute , 3700 San Martin Dr., Baltimore, MD 21218, USA
- K. Kohno
- ORCiD
- Institute of Astronomy, Graduate School of Science, The University of Tokyo , 2-21-1 Osawa, Mitaka, Tokyo 181-0015, Japan; Research Center for the Early Universe, Graduate School of Science, The University of Tokyo , 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
- V. Kokorev
- ORCiD
- Kapteyn Astronomical Institute, University of Groningen , PO Box 800, 9700 AV Groningen, The Netherlands
- M. M. Lee
- ORCiD
- Cosmic Dawn Center (DAWN) , Denmark ; [email protected]; DTU-Space, Technical University of Denmark , Elektrovej 327, DK-2800, Kgs. Lyngby, Denmark
- G. E. Magdis
- ORCiD
- Cosmic Dawn Center (DAWN) , Denmark ; [email protected]; Niels Bohr Institute, University of Copenhagen , Jagtvej 128, DK-2200 Copenhagen N, Denmark; DTU-Space, Technical University of Denmark , Elektrovej 327, DK-2800, Kgs. Lyngby, Denmark
- E. J. Nelson
- ORCiD
- Department for Astrophysical and Planetary Science, University of Colorado , Boulder, CO 80309, USA
- F. Rizzo
- ORCiD
- Cosmic Dawn Center (DAWN) , Denmark ; [email protected]; Niels Bohr Institute, University of Copenhagen , Jagtvej 128, DK-2200 Copenhagen N, Denmark
- R. L. Sanders
- ORCiD
- Department of Physics and Astronomy, University of California , Los Angeles, 430 Portola Plaza, Los Angeles, CA 90095, USA; Department of Physics, University of California , Davis, 1 Shields Ave., Davis, CA 95616, USA
- D. Schaerer
- ORCiD
- Observatoire de Genève, Université de Genève , Chemin Pegasi 51, 1290 Versoix, Switzerland; CNRS , IRAP, 14 Ave. E. Belin, F-31400 Toulouse, France
- A. E. Shapley
- ORCiD
- Department of Physics and Astronomy, University of California , Los Angeles, 430 Portola Plaza, Los Angeles, CA 90095, USA
- V. B. Strait
- ORCiD
- Cosmic Dawn Center (DAWN) , Denmark ; [email protected]; Niels Bohr Institute, University of Copenhagen , Jagtvej 128, DK-2200 Copenhagen N, Denmark
- S. Toft
- ORCiD
- Cosmic Dawn Center (DAWN) , Denmark ; [email protected]; Niels Bohr Institute, University of Copenhagen , Jagtvej 128, DK-2200 Copenhagen N, Denmark
- F. Valentino
- ORCiD
- Cosmic Dawn Center (DAWN) , Denmark ; [email protected]; Niels Bohr Institute, University of Copenhagen , Jagtvej 128, DK-2200 Copenhagen N, Denmark; European Southern Observatory , Karl-Schwarzschild-Str. 2, D-85748 Garching bei Munchen, Germany
- A. van der Wel
- ORCiD
- Sterrenkundig Observatorium, Universiteit Gent , Krijgslaan 281 S9, B-9000 Gent, Belgium
- A. P. Vijayan
- ORCiD
- Cosmic Dawn Center (DAWN) , Denmark ; [email protected]; DTU-Space, Technical University of Denmark , Elektrovej 327, DK-2800, Kgs. Lyngby, Denmark
- D. Watson
- ORCiD
- Cosmic Dawn Center (DAWN) , Denmark ; [email protected]; Niels Bohr Institute, University of Copenhagen , Jagtvej 128, DK-2200 Copenhagen N, Denmark
- F. E. Bauer
- ORCiD
- Instituto de Astrofísica, Facultad de Física, Pontificia Universidad Católica de Chile , Campus San Joaquín, Av. Vicuña Mackenna 4860, Macul Santiago, 7820436, Chile; Centro de Astroingeniería, Facultad de Física, Pontificia Universidad Católica de Chile , Campus San Joaquín, Av. Vicuña Mackenna 4860, Macul Santiago, 7820436, Chile; Millennium Institute of Astrophysics , Nuncio Monse nor Sótero Sanz 100, Of. 104, Providencia, Santiago, Chile
- C. R. Christiansen
- Cosmic Dawn Center (DAWN) , Denmark ; [email protected]; Niels Bohr Institute, University of Copenhagen , Jagtvej 128, DK-2200 Copenhagen N, Denmark
- S. N. Wilson
- ORCiD
- Cosmic Dawn Center (DAWN) , Denmark ; [email protected]; Niels Bohr Institute, University of Copenhagen , Jagtvej 128, DK-2200 Copenhagen N, Denmark
- DOI
- https://doi.org/10.3847/2041-8213/acb2cf
- Journal volume & issue
-
Vol. 944,
no. 2
p. L30
Abstract
We present a joint analysis of the galaxy S04590 at z = 8.496 based on NIRSpec, NIRCam, and NIRISS observations obtained as part of the Early Release Observations program of the James Webb Space Telescope (JWST) and the far-infrared [C ii ] 158 μ m emission line detected by dedicated Atacama Large Millimeter/submillimeter Array (ALMA) observations. We determine the physical properties of S04590 from modeling of the spectral energy distribution (SED) and through the redshifted optical nebular emission lines detected with JWST/NIRSpec. The best-fit SED model reveals a low-mass ( M _⋆ = 10 ^7.2 –10 ^8 M _⊙ ) galaxy with a low oxygen abundance of $12+\mathrm{log}({\rm{O}}/{\rm{H}})={7.16}_{-0.12}^{+0.10}$ derived from the strong nebular and auroral emission lines. Assuming that [C ii ] effectively traces the interstellar medium, we estimate the total gas mass of the galaxy to be M _gas = (8.0 ± 4.0) × 10 ^8 M _⊙ based on the luminosity and spatial extent of [C ii ]. This yields an exceptionally high gas fraction, f _gas = M _gas /( M _gas + M _⋆ ) ≳ 90%, though one still consistent with the range expected for low metallicity. We further derive the metal mass of the galaxy based on the gas mass and gas-phase metallicity, which we find to be consistent with the expected metal production from Type II supernovae. Finally, we make the first constraints on the dust-to-gas (DTG) and dust-to-metal (DTM) ratios of galaxies in the epoch of reionization at z ≳ 6, showing overall low mass ratios of logDTG < −3.8 and logDTM < −0.5, though they are consistent with established scaling relations and in particular with those of the local metal-poor galaxy I Zwicky 18. Our analysis highlights the synergy between ALMA and JWST in characterizing the gas, metal, and stellar content of the first generation of galaxies.
Keywords
- High-redshift galaxies
- Galaxies
- Interstellar medium
- Star formation
- Galaxy formation
- Galaxy evolution
