Nakajima, K. & Maiolino, R. Diagnostics for PopIII galaxies and direct collapse black holes in the early Universe. Mon. Not. R. Astron. Soc. 513, 5134–5147 (2022).
Heger, A. & Woosley, S. E. Nucleosynthesis and evolution of massive metal-free stars. Astrophys. J. 724, 341–373 (2010).
Vanni, I., Salvadori, S., Skúladóttir, Á., Rossi, M. & Koutsouridou, I. Characterizing the true descendants of the first stars. Mon. Not. R. Astron. Soc. 526, 2620–2644 (2023).
D’Eugenio, F. et al. JADES: carbon enrichment 350 Myr after the Big Bang. Astron. Astrophys. 689, 152 (2024).
Curtis-Lake, E. et al. Spectroscopic confirmation of four metal-poor galaxies at z = 10.3–13.2. Nat. Astron. 7, 622–632 (2023).
Harikane, Y. et al. Pure spectroscopic constraints on UV luminosity functions and cosmic star formation history from 25 galaxies at zspec = 8.61–13.20 confirmed with JWST/NIRSpec. Astrophys. J. 960, 56 (2024).
Carniani, S. et al. Spectroscopic confirmation of two luminous galaxies at a redshift of 14. Nature 633, 318–322 (2024).
Naidu, R. P. et al. A cosmic miracle: a remarkably luminous galaxy at zspec = 14.44 confirmed with JWST. Open J. Astrophys. 9, 56033 (2026).
Nakajima, K. et al. JWST census for the mass–metallicity star formation relations at z = 4–10 with self-consistent flux calibration and proper metallicity calibrators. Astrophys. J. Suppl. Ser. 269, 33 (2023).
Curti, M. et al. JADES: Insights into the low-mass end of the mass–metallicity–SFR relation at 3 < z < 10 from deep JWST/NIRSpec spectroscopy. Astron. Astrophys. 684, 75 (2024).
Maiolino, R. et al. JADES. Possible population III signatures at z = 10.6 in the halo of GN-z11. Astron. Astrophys. 687, 67 (2024).
Oesch, P. A. et al. A remarkably luminous galaxy at z = 11.1 measured with Hubble Space Telescope grism spectroscopy. Astrophys. J. 819, 129 (2016).
Bunker, A. J. et al. JADES NIRSpec spectroscopy of GN-z11: Lyman-α emission and possible enhanced nitrogen abundance in a z = 10.60 luminous galaxy. Astron. Astrophys. 677, 88 (2023).
Schaerer, D. The transition from population III to normal galaxies: Lyα and He II emission and the ionising properties of high redshift starburst galaxies. Astron. Astrophys. 397, 527–538 (2003).
Inoue, A. K. Rest-frame ultraviolet-to-optical spectral characteristics of extremely metal-poor and metal-free galaxies. Mon. Not. R. Astron. Soc. 415, 2920–2931 (2011).
Nishigaki, M. et al. EMPRESS. XI. SDSS and JWST search for local and z ∼ 4–5 extremely metal-poor galaxies (EMPGs): clustering and chemical properties of local EMPGs. Astrophys. J. 952, 11 (2023).
Fujimoto, S. et al. GLIMPSE: an ultra-faint ≃105 M⊙ Pop III galaxy candidate and first constraints on the Pop III UV luminosity function at z ≃ 6−7. Astrophys. J. 989, 46 (2025).
Hsiao, T. Y.-Y. et al. SAPPHIRES: extremely metal-poor galaxy candidates with 12 + log(O/H) < 7.0 at z ~ 5−7 from deep JWST/NIRCam grism observations. Preprint at http://arxiv.org/abs/2505.03873 (2025).
Trussler, J. A. A. et al. On the observability and identification of population III galaxies with JWST. Mon. Not. R. Astron. Soc. 525, 5328–5352 (2023).
Vanzella, E. et al. An extremely metal-poor star complex in the reionization era: approaching population III stars with JWST. Astron. Astrophys. 678, 173 (2023).
Jakobsen, P., Wright, R., Zeidler, P. & Zincke, C. The near-infrared spectrograph (NIRSpec) on the James Webb Space Telescope. I. Overview of the instrument and its capabilities. Astron. Astrophys. 661, 80 (2022).
Maiolino, R. & Mannucci, F. De re metallica: the cosmic chemical evolution of galaxies. Astron. Astrophys. Rev. 27, 3 (2019).
Álvarez-Márquez, J. et al. Insight into the starburst nature of galaxy GN-z11 with JWST MIRI spectroscopy. Astron. Astrophys. 695, 250 (2025).
Hsiao, T. Y.-Y. et al. JWST MIRI detections of Hα and [O III] and a direct metallicity measurement of the z = 10.17 lensed galaxy MACS0647–JD. Astrophys. J. 973, 81 (2024).
Zavala, J. A. et al. A luminous and young galaxy at z = 12.33 revealed by a JWST/MIRI detection of Hα and [O III]. Nat. Astron. 9, 155–164 (2025).
Vanzella, E. et al. Extreme ionizing properties of a metal-poor, MUV ≃ −12 star complex in the first gigayear. Astron. Astrophys. 691, 251 (2024).
Schaerer, D., Guibert, J., Marques-Chaves, R. & Martins, F. Observable and ionizing properties of star-forming galaxies with very massive stars and different initial mass functions. Astron. Astrophys. 693, 271 (2025).
Meynet, G. & Maeder, A. Stellar evolution with rotation. VIII. Models at Z = 10−5 and CNO yields for early galactic evolution. Astron. Astrophys. 390, 561–583 (2002).
Akerman, C. J., Carigi, L., Nissen, P. E., Pettini, M. & Asplund, M. The evolution of the C/O ratio in metal-poor halo stars. Astron. Astrophys. 414, 931–942 (2004).
Kobayashi, C., Karakas, A. I. & Lugaro, M. The origin of elements from carbon to uranium. Astrophys. J. 900, 179 (2020).
Schaerer, D. On the properties of massive population III stars and metal-free stellar populations. Astron. Astrophys. 382, 28–42 (2002).
Heger, A. & Woosley, S. E. The nucleosynthetic signature of population III. Astrophys. J. 567, 532–543 (2002).
Woosley, S. E., Heger, A. & Weaver, T. A. The evolution and explosion of massive stars. Rev. Mod. Phys. 74, 1015–1071 (2002).
Umeda, H. & Nomoto, K. Nucleosynthesis of zinc and iron peak elements in population III type II supernovae: comparison with abundances of very metal poor halo stars. Astrophys. J. 565, 385–404 (2002).
Umeda, H. & Nomoto, K. First-generation black-hole-forming supernovae and the metal abundance pattern of a very iron-poor star. Nature 422, 871–873 (2003).
Iwamoto, N., Umeda, H., Tominaga, N., Nomoto, K. & Maeda, K. The first chemical enrichment in the Universe and the formation of hyper metal-poor stars. Science 309, 451–453 (2005).
Ishigaki, M. N., Tominaga, N., Kobayashi, C. & Nomoto, K. Faint population III supernovae as the origin of the most iron-poor stars. Astrophys. J. 792, 32 (2014).
Ji, X. et al. GA-NIFS: an extremely nitrogen-loud and chemically stratified galaxy at z ∼ 5.55. Mon. Not. R. Astron. Soc. 535, 881–908 (2024).
Katz, H., Kimm, T., Ellis, R. S., Devriendt, J. & Slyz, A. The challenges of identifying population III stars in the early Universe. Mon. Not. R. Astron. Soc. 524, 351–360 (2023).
Rusta, E. et al. Metal-polluted population III galaxies and how to find them. Astrophys. J. 989, 32 (2025).
Maiolino, R. et al. A black hole in a near-pristine galaxy 700 million years after the Big Bang. Mon. Not. R. Astron. Soc. (in the press).
Simon, J. D. The faintest dwarf galaxies. Annu. Rev. Astron. Astrophys. 57, 375–415 (2019).
Jeon, M., Besla, G. & Bromm, V. Connecting the first galaxies with ultrafaint dwarfs in the Local Group: chemical signatures of population III stars. Astrophys. J. 848, 85 (2017).
Rossi, M., Salvadori, S., Skúladóttir, Á., Vanni, I. & Koutsouridou, I. Hidden population III descendants in ultrafaint dwarf galaxies. Astrophys. J. 987, 121 (2025).
Heiger, M. E. et al. Not-so-heavy metal(s): chemical abundances in the ultra-faint dwarf galaxies Eridanus IV and Centaurus I. Preprint at http://arxiv.org/abs/2508.11012 (2025).
Bosman, S. E. I. et al. Hydrogen reionization ends by z = 5.3: Lyman-α optical depth measured by the XQR-30 sample. Mon. Not. R. Astron. Soc. 514, 55–76 (2022).
Bovill, M. S. & Ricotti, M. Pre-reionization fossils, ultra-faint dwarfs, and the missing galactic satellite problem. Astrophys. J. 693, 1859–1870 (2009).
Salvadori, S. & Ferrara, A. Ultra faint dwarfs: probing early cosmic star formation. Mon. Not. R. Astron. Soc. 395, 6–10 (2009).
Chieffi, A. & Limongi, M. The explosive yields produced by the first generation of core collapse supernovae and the chemical composition of extremely metal poor stars. Astrophys. J. 577, 281–294 (2002).
Oke, J. B. & Gunn, J. E. Secondary standard stars for absolute spectrophotometry. Astrophys. J. 266, 713–717 (1983).
Asplund, M., Grevesse, N., Sauval, A. J. & Scott, P. The chemical composition of the Sun. Annu. Rev. Astron. Astrophys. 47, 481–522 (2009).
Vanzella, E. et al. Candidate population III stellar complex at z = 6.629 in the MUSE deep lensed field. Mon. Not. R. Astron. Soc. 494, 81–85 (2020).
Bergamini, P. et al. New high-precision strong lensing modeling of Abell 2744. Preparing for JWST observations. Astron. Astrophys. 670, 60 (2023).
Sanders, R. L., Shapley, A. E., Topping, M. W., Reddy, N. A. & Brammer, G. B. Direct Te-based metallicities of z = 2–9 galaxies with JWST/NIRSpec: empirical metallicity calibrations applicable from reionization to cosmic noon. Astrophys. J. 962, 24 (2024).
Chakraborty, P. et al. Unveiling the cosmic chemistry. II. ‘Direct’ Te-based metallicity of galaxies at 3 < z < 10 with JWST/NIRSpec. Astrophys. J. 985, 24 (2025).
Nakajima, K. et al. EMPRESS. V. Metallicity diagnostics of galaxies over 12 + log(O/H) = 6.9–8.9 established by a local galaxy census: preparing for JWST spectroscopy. Astrophys. J. Suppl. Ser. 262, 3 (2022).
Hirschmann, M., Charlot, S. & Somerville, R. S. High-redshift metallicity calibrations for JWST spectra: insights from line emission in cosmological simulations. Mon. Not. R. Astron. Soc. 526, 3504–3518 (2023).
Eldridge, J. J. et al. Binary Population and Spectral Synthesis Version 2.1: construction, observational verification, and new results. Publ. Astron. Soc. Aust. 34, 058 (2017).
Stanway, E. R. & Eldridge, J. J. Re-evaluating old stellar populations. Mon. Not. R. Astron. Soc. 479, 75–93 (2018).
Andrews, B. H. & Martini, P. The mass–metallicity relation with the direct method on stacked spectra of SDSS galaxies. Astrophys. J. 765, 140 (2013).
Pérez-Montero, E. Deriving model-based Te-consistent chemical abundances in ionized gaseous nebulae. Mon. Not. R. Astron. Soc. 441, 2663–2675 (2014).
Sanders, R. L. et al. The MOSDEF survey: direct-method metallicities and ISM conditions at z ~ 1.5–3.5. Mon. Not. R. Astron. Soc. 491, 1427–1455 (2020).
Nishigaki, M. et al. DREAMS.II. Galaxy demographics from direct Te-based metallicities at z~2–10: tracing the evolution of the mass-metallicity and fundamental relations. Preprint at https://doi.org/10.48550/arXiv.2512.12983 (2025).
Morishita, T. et al. Diverse oxygen abundance in early galaxies unveiled by auroral line analysis with JWST. Astrophys. J. 971, 43 (2024).
Sarkar, A. et al. Unveiling the cosmic chemistry: revisiting the mass–metallicity relation with JWST/NIRSpec at 4 < z < 10. Astrophys. J. 978, 136 (2025).
Venturi, G. et al. Gas-phase metallicity gradients in galaxies at z ~ 6–8. Astron. Astrophys. 691, 19 (2024).
Marconcini, C. et al. GA-NIFS: the interplay between merger, star formation, and chemical enrichment in MACS1149-JD1 at z = 9.11 with JWST/NIRSpec. Mon. Not. R. Astron. Soc. 533, 2488–2501 (2024).
Williams, H. et al. A magnified compact galaxy at redshift 9.51 with strong nebular emission lines. Science 380, 416–420 (2023).
Schaerer, D., Marques-Chaves, R., Xiao, M. & Korber, D. Discovery of a new N-emitter in the epoch of reionization. Astron. Astrophys. 687, 11 (2024).
Mowla, L. et al. Formation of a low-mass galaxy from star clusters in a 600-million-year-old Universe. Nature 636, 332–336 (2024).
Cullen, F. et al. The JWST EXCELS survey: an extremely metal-poor galaxy at z = 8.271 hosting an unusual population of massive stars. Mon. Not. R. Astron. Soc. 540, 2176–2194 (2025).
Willott, C. J. et al. In search of the first stars: an ultra-compact and very low metallicity Lyman-α emitter deep within the epoch of reionization. Astrophys. J. 988, 26 (2025).
Pérez-Montero, E. & Amorín, R. Using photo-ionisation models to derive carbon and oxygen gas-phase abundances in the rest UV. Mon. Not. R. Astron. Soc. 467, 1287–1293 (2017).
Arellano-Córdova, K. Z. et al. A first look at the abundance pattern—O/H, C/O, and Ne/O-in z > 7 galaxies with JWST/NIRSpec. Astrophys. J. 940, 23 (2022).
Jones, T. et al. Early results from GLASS-JWST. XXI. Rapid asembly of a galaxy at z = 6.23 revealed by its C/O abundance. Astrophys. J. 951, 17 (2023).
Isobe, Y. et al. JWST identification of extremely low C/N galaxies with [N/O] ≳0.5 at z ∼ 6–10 evidencing the early CNO-cycle enrichment and a connection with globular cluster formation. Astrophys. J. 959, 100 (2023).
Stiavelli, M. et al. The puzzling properties of the MACS1149-JD1 galaxy at z = 9.11. Astrophys. J. 957, 18 (2023).
Castellano, M. et al. JWST NIRSpec spectroscopy of the remarkable bright galaxy GHZ2/GLASS-z12 at redshift 12.34. Astrophys. J. 972, 143 (2024).
Topping, M. W. et al. Metal-poor star formation at z > 6 with JWST: new insight into hard radiation fields and nitrogen enrichment on 20 pc scales. Mon. Not. R. Astron. Soc. 529, 3301–3322 (2024).
Hsiao, T. Y.-Y. et al. First direct carbon abundance measured at z > 10 in the lensed galaxy MACS0647-JD. Astrophys. J. 993, 70 (2025).
Curti, M. et al. JADES: the star formation and chemical enrichment history of a luminous galaxy at z ~ 9.43 probed by ultra-deep JWST/NIRSpec spectroscopy. Astron. Astrophys. 697, 89 (2025).
Carniani, S. et al. The eventful life of a luminous galaxy at z = 14: metal enrichment, feedback, and low gas fraction? Astron. Astrophys. 696, 87 (2025).
Cooke, R. J., Pettini, M. & Steidel, C. C. Discovery of the most metal-poor damped Lyman-α system. Mon. Not. R. Astron. Soc. 467, 802–811 (2017).
Gustafsson, B., Karlsson, T., Olsson, E., Edvardsson, B. & Ryde, N. The origin of carbon, investigated by spectral analysis of solar-type stars in the Galactic disk. Astron. Astrophys. 342, 426–439 (1999).
Spite, M. et al. First stars. VI. Abundances of C, N, O, Li, and mixing in extremely metal-poor giants. Galactic evolution of the light elements. Astron. Astrophys. 430, 655–668 (2005).
Bensby, T. & Feltzing, S. The origin and chemical evolution of carbon in the Galactic thin and thick discs. Mon. Not. R. Astron. Soc. 367, 1181–1193 (2006).
Fabbian, D., Nissen, P. E., Asplund, M., Pettini, M. & Akerman, C. The C/O ratio at low metallicity: constraints on early chemical evolution from observations of Galactic halo stars. Astron. Astrophys. 500, 1143–1155 (2009).
Nissen, P. E., Chen, Y. Q., Carigi, L., Schuster, W. J. & Zhao, G. Carbon and oxygen abundances in stellar populations. Astron. Astrophys. 568, 25 (2014).
Frebel, A., Simon, J. D. & Kirby, E. N. Segue 1: an unevolved fossil galaxy from the early Universe. Astrophys. J. 786, 74 (2014).
Tsujimoto, T. & Shigeyama, T. Enrichment history of r-process elements shaped by a merger of neutron star pairs. Astron. Astrophys. 565, 5 (2014).
Ferland, G. J. et al. CLOUDY 90: numerical simulation of plasmas and their spectra. Publ. Astron. Soc. Pac. 110, 761–778 (1998).
Ferland, G. J. et al. The 2013 release of Cloudy. Rev. Mex. Astron. Astrofís. 49, 137–163 (2013).
Dopita, M. A. et al. Modeling the pan-spectral energy distribution of starburst galaxies. III. Emission line diagnostics of ensembles of evolving H II regions. Astrophys. J. Suppl. Ser. 167, 177–200 (2006).
Jenkins, E. B. A unified representation of gas-phase element depletions in the interstellar medium. Astrophys. J. 700, 1299–1348 (2009).
van Hoof, P. A. M., Weingartner, J. C., Martin, P. G., Volk, K. & Ferland, G. J. Grain size distributions and photoelectric heating in ionized media. Mon. Not. R. Astron. Soc. 350, 1330–1341 (2004).
Nakajima, K. Reduced JWST/NIRSpec spectrum for ‘An ultra-faint, chemically primitive galaxy forming in the reionization era’. Zenodo https://doi.org/10.5281/zenodo.18831461 (2026).
Astropy Collaboration Astropy: a community Python package for astronomy. Astron. Astrophys. 558, 33 (2013).
Astropy Collaboration The Astropy project: building an open-science project and status of the v2.0 core package. Astron. J. 156, 123 (2018).
Astropy Collaboration The Astropy project: sustaining and growing a community-oriented open-source project and the latest major release (v5.0) of the core package. Astrophys. J. 935, 167 (2022).
Luridiana, V., Morisset, C. & Shaw, R. A. PyNeb: a new tool for analyzing emission lines. I. Code description and validation of results. Astron. Astrophys. 573, 42 (2015).
Gessey-Jones, T. et al. Impact of the primordial stellar initial mass function on the 21-cm signal. Mon. Not. R. Astron. Soc. 516, 841–860 (2022).