JWST NIRSpec Spectroscopy of the Remarkable Bright Galaxy GHZ2/GLASS-z12 at Redshift 12.34

Abstract We spectroscopically confirm the M UV = −20.5 mag galaxy GHZ2/GLASS-z12 to be at redshift z = 12.34. The source was selected via NIRCam photometry in GLASS-JWST Early Release Science data, providing the first evidence of a surprising abundance of bright galaxies at z ≳ 10. The NIRSpec PRISM spectrum shows detections of N iv , C iv , He ii , O iii , C iii , O ii , and Ne iii lines and the first detection at high redshift of the O iii Bowen fluorescence line at 3133 Å rest frame. The prominent C iv line with rest-frame equivalent width (EW) ≈ 46 Å puts GHZ2 in the category of extreme C iv emitters. GHZ2 displays UV lines with EWs that are only found in active galactic nuclei (AGNs) or composite objects at low/intermediate redshifts. The UV line-intensity ratios are compatible with both AGNs and star formation in a low-metallicity environment, with the low limit on the [Ne iv ]/[N iv ] ratio favoring a stellar origin of the ionizing photons. We discuss a possible scenario in which the high ionizing output is due to low-metallicity stars forming in a dense environment. We estimate a metallicity ≲0.1 Z / Z ⊙ , a high ionization parameter log U > −2, a N/O abundance 4–5 times the solar value, and a subsolar C/O ratio similar to the recently discovered class of nitrogen-enhanced objects. Considering its abundance patterns and the high stellar mass density (10 4 M ⊙ pc −2 ), GHZ2 is an ideal formation site for the progenitors of today's globular clusters. The remarkable brightness of GHZ2 makes it a “Rosetta stone” for understanding the physics of galaxy formation within just 360 Myr after the Big Bang.

Authors

Institutions

Publication Details

Journal
The Astrophysical Journal
Published
2024-09-01
DOI
https://doi.org/10.3847/1538-4357/ad5f88
Citations
121
Primary Topic
Galaxies: Formation, Evolution, Phenomena
Type
article
Field-Weighted Citation Impact
40.11

Funders

Controls
|||
ALL TIME
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
article

JWST NIRSpec Spectroscopy of the Remarkable Bright Galaxy GHZ2/GLASS-z12 at Redshift 12.34

E. Merlin, Guido Roberts-Borsani, L. Pentericci, P. Rosati et al.
121 citations
The Astrophysical Journal
Galaxies: Formation, Evolution, Phenomena
40.11
article

JWST NIRSpec Spectroscopy of the Remarkable Bright Galaxy GHZ2/GLASS-z12 at Redshift 12.34

E. Merlin, Guido Roberts-Borsani, L. Pentericci, P. Rosati, Patrick L. Kelly, Karl Glazebrook, Jorge A. Zavala, Charlotte Mason, E. Sani, Tommaso Treu, Pablo Arrabal Haro, D. Paris, Ilsang Yoon, A. V. Filippenko, Themiya Nanayakkara, Takahiro Morishita, C. Grillo, Matthew A. Malkan, Antonello Calabrò, M. Castellano, P. Bergamini, Xin Wang, G. Cupani, E. Vanzella, Mark Dickinson, Mario Llerena, A. Fontana, Tom J. L. C. Bakx, Sara Mascia, P. Santini, Lorenzo Napolitano
article en
121 citations

Abstract

Abstract We spectroscopically confirm the M UV = −20.5 mag galaxy GHZ2/GLASS-z12 to be at redshift z = 12.34. The source was selected via NIRCam photometry in GLASS-JWST Early Release Science data, providing the first evidence of a surprising abundance of bright galaxies at z ≳ 10. The NIRSpec PRISM spectrum shows detections of N iv , C iv , He ii , O iii , C iii , O ii , and Ne iii lines and the first detection at high redshift of the O iii Bowen fluorescence line at 3133 Å rest frame. The prominent C iv line with rest-frame equivalent width (EW) ≈ 46 Å puts GHZ2 in the category of extreme C iv emitters. GHZ2 displays UV lines with EWs that are only found in active galactic nuclei (AGNs) or composite objects at low/intermediate redshifts. The UV line-intensity ratios are compatible with both AGNs and star formation in a low-metallicity environment, with the low limit on the [Ne iv ]/[N iv ] ratio favoring a stellar origin of the ionizing photons. We discuss a possible scenario in which the high ionizing output is due to low-metallicity stars forming in a dense environment. We estimate a metallicity ≲0.1 Z / Z ⊙ , a high ionization parameter log U > −2, a N/O abundance 4–5 times the solar value, and a subsolar C/O ratio similar to the recently discovered class of nitrogen-enhanced objects. Considering its abundance patterns and the high stellar mass density (10 4 M ⊙ pc −2 ), GHZ2 is an ideal formation site for the progenitors of today's globular clusters. The remarkable brightness of GHZ2 makes it a “Rosetta stone” for understanding the physics of galaxy formation within just 360 Myr after the Big Bang.

The Astrophysical JournalVol. 972(2)
University of Geneva (CH), California Institute of Technology (US), University of Copenhagen (DK), University of Minnesota (US), University of California, Los Angeles (US), University of Milan (IT), Chinese Academy of Sciences (CN), University of Ferrara (IT), Beijing Normal University (CN), National Radio Astronomy Observatory (US), Astronomical Observatory of Rome (IT), Trieste Astronomical Observatory (IT), European Southern Observatory (CL), Community Science and Data Center (US), NSF NOIRLab (US), Institute for Fundamental Physics of the Universe (IT), National Astronomical Observatory of Japan (JP), National Astronomical Observatories (CN), University of Chinese Academy of Sciences (CN), Infrared Processing and Analysis Center (US), Osservatorio di Astrofisica e Scienza dello Spazio, Swinburne University of Technology (AU), Chalmers University of Technology (SE), Sapienza University of Rome (IT), National Institute for Astrophysics (IT), University of California, Berkeley (US)
National Aeronautics and Space Administration, Villum Fonden, Space Telescope Science Institute, European Commission, National Research Foundation, Danmarks Grundforskningsfond, Ministero dell’Istruzione, dell’Università e della Ricerca
Openalex Percentile: Top 0%
Galaxies: Formation, Evolution, Phenomena
40.11
DOIOpen Access PDFOpenAlex
AI Navigator

Ask Laika to Summarize, Analyze, and Connect papers live on the map.

Summarize Papers & Methodologies

Extract key findings, datasets, and comparative methods across publications.

Benchmark Rankings & Visual Analytics

Rank top research institutions, authors, funders, topics, and journals by Field-Weighted Citation Impact (FWCI) and paper volume with instant charts.

Connect Distant Disciplines

Bridge topological clusters on the map to find hidden collaborative intersections.