Ionizing Photon Production Efficiencies and Chemical Abundances at Cosmic Dawn Revealed by Ultradeep Rest-frame Optical Spectroscopy of JADES-GS-z14-0
Year: 2026
Type: article
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
Authors: Jakob M. Helton, Jane E. Morrison, Kevin N. Hainline, Francesco D’Eugenio, George H. Rieke, Stacey Alberts, Stefano Carniani, Joel Leja, Yijia 轶佳 Li 李, Pierluigi Rinaldi, Jan Scholtz, Meredith Stone, Christopher N. A. Willmer, Zihao Wu, William M. Baker, Andrew J. Bunker, Stephane Charlot, Jacopo Chevallard, Nikko J. Cleri, Mirko Curti, Emma Curtis-Lake, Eiichi Egami, Daniel J. Eisenstein, Peter Jakobsen, Zhiyuan Ji, Benjamin D. Johnson, Nimisha Kumari, Xiaojing Lin, Jianwei Lyu, Roberto Maiolino, Michael Maseda, Pablo G. Pérez-González, Marcia J. Rieke, Brant Robertson, Aayush Saxena, Fengwu Sun, Sandro Tacchella, Hannah Übler, Giacomo Venturi, Christina C. Williams, Chris Willott, Joris Witstok, Yongda Zhu
Institutions: Pennsylvania State University, University of Arizona, University of Cambridge, Space Telescope Science Institute, Scuola Normale Superiore, Northwestern University, Center for Astrophysics Harvard & Smithsonian, University of Copenhagen, University of Oxford, Sorbonne Université, European Southern Observatory, European Southern Observatory, University of Hertfordshire, Tsinghua University, University College London, University of Wisconsin–Madison, Centro de Astrobiología, University of California System, Max Planck Institute for Extraterrestrial Physics, NSF NOIRLab, Herzberg Institute of Astrophysics, National Research Council Canada
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $2,400
Funders: National Science Foundation, National Aeronautics and Space Administration, University of California, Santa Cruz, University of Arizona, Pennsylvania State University, Villum Fonden, Space Telescope Science Institute, UK Research and Innovation, Royal Society, European Commission, National Research Foundation, Danmarks Grundforskningsfond, Nuclear Safety and Security Commission, Ministerio de Ciencia e Innovación, Goddard Space Flight Center, Science and Technology Facilities Council, Agencia Estatal de Investigación
Awards: G103270039, G1175115578, G1199145202, G121809054, G1245046120, G1338664626, G1409812818, G1632446036, G1700342535, G1812695587, G1824424381, G1839900423, G1855990336, G2021250021, G210041235, G2144673021, G2262748287, G2272116534, G2309174360, G2447233868, G2469010403, Star formation in galaxies from the Epoch of Reionisation to the present day with JWST, G2550756520, G256731684, G2601397997, G2650114919, G2660088634, G2660406951, G279363373, G300979063, G3152952368, G34346518, G3452655474, G3480869486, G3518538256, G3575130984, G3660973570, G3681454997, G3775832800, G3823816291, G4035329295, G4042783231, G4161023950, G425668148, G430777504, G434337789, G4442677895, G4526231891, G4915654406, G5080475149, G5180915604, G5195188938, G5421974903, G5480708011, G5568641063, G5663025379, G6115201310, G6307073466, 1. SCIENCE INVESTIGATION: SUMMARY IN MY ORIGINAL PROPOSAL WRITTEN PRIOR TO THE LAUNCH OF SPITZER I PLANNED A JWST PROGRAM ON ACTIVE GALACTIC NUCLEI (AGN) AND THEIR HOST GALAXIES BUILDING ON THEN-FUTURE SPITZER OBSERVATIONS. TOWARD THE END OF THE SPITZER COLD MISSION AS THE PI FOR THE MIPS INSTRUMENT I HAD LED SUBSTANTIAL PROGRAMS ON BOTH EXTRAGALACTIC OBSERVATIONS AND DEBRIS DISKS SO I PROPOSED TO EXPAND MY JWST EFFORT TO INCLUDE BOTH AN EXPANSION THAT WAS APPROVED BY ED WEILER ON OCTOBER 16 2009. THE FOLLOWING PROGRAM THEREFORE INCLUDES BOTH OF THESE THEMES. SINCE BOTH PROPOSALS WERE WRITTEN MAJOR NEW CAPABILITIES HAVE ANSWERED SOME OF THE PREVIOUS SCIENTIFIC QUESTIONS AND POSED NEW ONES. IN THE EXTRAGALACTIC ARENA THESE INCLUDE SPITZER ITSELF HERSCHEL THE EXPANDED CAPABILITIES OF THE JVLA AND ALMA. FOR DEBRIS DISKS THE MOST IMPORTANT ARE HERSCHEL ALMA AND HIGH PERFORMANCE ADAPTIVE OPTICS. THEREFORE THE MATERIAL IN THIS PROPOSAL IS RE-THOUGHT TO PROVIDE A PROGRAM AT THE CUTTING EDGE OF THE CURRENT PROBLEMS IN THESE AREAS. EACH OF THE INDIVIDUAL INVESTIGATIONS DESCRIBED BELOW IS DESCRIBED IN A DETAILED INTERNAL REPORT AND IS READY FOR DETAILED OBSERVATION PLANNING. THIS PROPOSAL GIVES A SUMMARY OF THE HIGH LEVEL GOALS AND REQUIRED OBSERVATIONS ONLY. IT INTENTIONALLY SOMEWHAT OVERSUBSCRIBES MY TIME ALLOTMENT TO ALLOW FOR COLLABORATIONS AND SHARED TIME AS WELL AS FURTHER OPTIMIZATION. ALTHOUGH THERE ARE A NUMBER OF INVESTIGATIONS MY RESEARCH GROUP HAS BEEN ACTIVE IN ALL OF THEM; I HAVE BOLD-FACED CITATIONS OF OUR RELEVANT WORK IN THE BIBLIOGRAPHY (ATTACHED AS APPENDIX A). IN ADDITION I WAS ASSIGNED AN ADDITIONAL 60 HOURS OF GTO TIME TO BE DISTRIBUTED AMONG (MOSTLY) YOUNG SCIENTISTS IN THE UNITED STATES WHO HAD MADE MAJOR COMMITMENTS IN SUPPORT OF MIRI (ROUGHLY PARALLEL TO THE GTO TIME FOR MIRI SUPPORT BY THE EUROPEAN CONSORTIUM (EC)). APPENDIX C INCLUDES SHORT STATUS REPORTS ON THEIR PLANS., G6464745819, G6687328476, G7084143925, G7113369193, G7322907961, G7678768968, G7709247530, G7907587068, G7935691682, G8537993047, MRI: Acquisition of a High Performance Computer for Computational Science at UC Santa Cruz, G8920660035, G8931419319, G897484643, G99296377
OpenAlex ID: W7164831357