The AURORA Survey

Authors

• Ryan L. Sanders, University of KentuckyFollow
• Alice E. Shapley, University of California, Los Angeles
• Michael W. Topping, University of Arizona
• Naveen A. Reddy, University of California Riverside
• Danielle A. Berg, University of Texas at Austin
• Ali Ahmad Khostovan, University of KentuckyFollow
• Rychard J. Bouwens, Leiden Observatory Research Institute
• Gabriel Brammer, Niels Bohr Institute
• Adam C. Carnall, University of Edinburgh
• Fergus Cullen, University of Edinburgh
• Romeel Davé, University of Edinburgh
• James S. Dunlop, University of Edinburgh
• Richard S. Ellis, University College London
• N. M. Förster Schreiber, Max Planck Institute for Extraterrestrial Physics
• Steven R. Furlanetto, University of California, Los Angeles
• Karl Glazebrook, Swinburne University of Technology
• Garth D. Illingworth, University of California
• Tucker Jones, University of California Davis
• Mariska Kriek, Leiden Observatory Research Institute
• Derek J. McLeod, University of Edinburgh
• Ross J. McLure, University of Edinburgh
• Desika Narayanan, University of Florida
• Pascal A. Oesch, Niels Bohr Institute
• Anthony J. Pahl, Carnegie Institution of Washington
• Max Pettini, Institute of Astronomy
• Daniel Schaerer, University of Geneva
• Daniel P. Stark, University of California Berkeley
• Charles C. Steidel, California Institute of Technology
• Mengtao Tang, University of Arizona
• Leonardo Clarke, University of California, Los Angeles
• Callum T. Donnan, NSF's National Optical-Infrared Astronomy Research Laboratory
• Emily Kehoe, University of California, Los Angeles

Abstract

We present detections of auroral emission lines of [O iii], [O ii], [S iii], and [S ii] in deep JWST/NIRSpec spectroscopy for 41 star-forming galaxies at z = 1.4–7.2 from the AURORA survey. We combine these new observations with 98 star-forming galaxies at z = 1.3–10.6 with detected auroral lines drawn from the literature to form a sample of 139 high-redshift galaxies with robust electron temperature and direct-method oxygen abundance determinations. This sample notably covers a wider dynamic range in metallicity than previous work, spanning 0.02–0.9 Z_⊙. We calibrate empirical relations between 19 emission-line ratios and oxygen abundance, providing a robust tool set to infer accurate gas-phase metallicities of high-redshift galaxies when auroral lines are not detected. While calibrations based on lines of α elements (O, Ne, S, Ar) appear reliable, we find significant scatter in calibrations involving lines of N driven by a high dispersion in N/O at fixed O/H, suggesting that N-based line ratios are less reliable tracers of the oxygen abundance at high redshift. These new high-redshift calibrations are notably offset from those based on typical z ∼ 0 galaxy and H ii region samples, and are better matched by samples of extreme local galaxies that are analogs of high-redshift sources. The new metallicity calibrations presented in this work pave the way for robust studies of galaxy chemical evolution in the early Universe, leading to a better understanding of baryon cycling and galaxy formation from Cosmic Noon through the Epoch of Reionization.

Document Type

Article

Publication Date

6-1-2026

Notes/Citation Information

Publisher Copyright: © 2026. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the https://creativecommons.org/licenses/by/4.0/. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.

Digital Object Identifier (DOI)

10.3847/1538-4357/ae66e2

Archival?

Archival

Repository Citation

Sanders, Ryan L.; Shapley, Alice E.; Topping, Michael W.; Reddy, Naveen A.; Berg, Danielle A.; Khostovan, Ali Ahmad; Bouwens, Rychard J.; Brammer, Gabriel; Carnall, Adam C.; Cullen, Fergus; Davé, Romeel; Dunlop, James S.; Ellis, Richard S.; Förster Schreiber, N. M.; Furlanetto, Steven R.; Glazebrook, Karl; Illingworth, Garth D.; Jones, Tucker; Kriek, Mariska; McLeod, Derek J.; McLure, Ross J.; Narayanan, Desika; Oesch, Pascal A.; Pahl, Anthony J.; Pettini, Max; Schaerer, Daniel; Stark, Daniel P.; Steidel, Charles C.; Tang, Mengtao; Clarke, Leonardo; Donnan, Callum T.; and Kehoe, Emily, "The AURORA Survey" (2026). Physics and Astronomy Faculty Publications. 773.
https://uknowledge.uky.edu/physastron_facpub/773