Flaugher, B. et al. The dark energy camera. Astron. J. 150, 150 (2015).
Beers, T. C., Preston, G. W. & Shectman, S. A. A search for stars of very low metal abundance. I. Astron. J. 90, 2089–2102 (1985).
Keller, S. C. et al. The SkyMapper Telescope and The Southern Sky Survey. Publ. Astron. Soc. Aust. 24, 1–12 (2007).
Starkenburg, E. et al. The Pristine survey I. Mining the Galaxy for the most metal-poor stars. Mon. Not. R. Astron. Soc. 471, 2587–2604 (2017).
Gaia Collaboration et al. Gaia Data Release 1. Summary of the astrometric, photometric, and survey properties. Astron. Astrophys. 595, A2 (2016).
Gaia Collaboration et al. Gaia Data Release 3. Summary of the content and survey properties. Astron. Astrophys. 674, A1 (2023).
Battaglia, G., Taibi, S., Thomas, G. F. & Fritz, T. K. Gaia early DR3 systemic motions of Local Group dwarf galaxies and orbital properties with a massive Large Magellanic Cloud. Astron. Astrophys. 657, A54 (2022).
Marshall, J. L. et al. McLean, I. S. & Casali, M. M. The MagE spectrograph. In Ground-based and Airborne Instrumentation for Astronomy II of Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series (eds McLean, I. S. & Casali, M. M.) 7014, 701454 (SPIE, 2008).
Pace, A. B. et al. Spectroscopic analysis of Pictor II: a very low metallicity ultra-faint dwarf galaxy bound to the Large Magellanic Cloud. Open J. Astrophys. 8, 112 (2025).
Vernet, J. et al. X-shooter, the new wide band intermediate resolution spectrograph at the ESO Very Large Telescope. Astron. Astrophys. 536, A105 (2011).
Cayrel, R. et al. First stars V—abundance patterns from C to Zn and supernova yields in the early Galaxy. Astron. Astrophys. 416, 1117–1138 (2004).
Heger, A. & Woosley, S. E. Nucleosynthesis and evolution of massive metal-free stars. Astrophys. J. 724, 341–373 (2010).
Ji, A. P., Frebel, A. & Bromm, V. Preserving chemical signatures of primordial star formation in the first low-mass stars. Mon. Not. R. Astron. Soc. 454, 659–674 (2015).
Koutsouridou, I. et al. The energy distribution of the first supernovae. Mon. Not. R. Astron. Soc. 525, 190–210 (2023).
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).
Brown, T. M. et al. The quenching of the ultra-faint dwarf galaxies in the reionization era. Astrophys. J. 796, 91 (2014).
Simon, J. D. & Geha, M. The kinematics of the ultra-faint Milky Way satellites: solving the missing satellite problem. Astrophys. J. 670, 313–331 (2007).
Searle, L. & Zinn, R. Composition of halo clusters and the formation of the galactic halo. Astrophys. J. 225, 357–379 (1978).
Simon, J. D. The faintest dwarf galaxies. Annu. Rev. Astron. Astrophys. 57, 375–415 (2019).
Hartwig, T. et al. Descendants of the first stars: the distinct chemical signature of second-generation stars. Mon. Not. R. Astron. Soc. 478, 1795–1810 (2018).
Bonifacio, P., Caffau, E., François, P. & Spite, M. The most metal-poor stars. Astron. Astrophys. Rev. 33, 2 (2025).
Beers, T. C. & Christlieb, N. The discovery and analysis of very metal-poor stars in the galaxy. Annu. Rev. Astron. Astrophys. 43, 531–580 (2005).
Cooke, R. J. & Madau, P. Carbon-enhanced metal-poor stars: relics from the dark ages. Astrophys. J. 791, 116 (2014).
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).
Meynet, G., Ekström, S. & Maeder, A. The early star generations: the dominant effect of rotation on the CNO yields. Astron. Astrophys. 447, 623–639 (2006).
Bromm, V. & Loeb, A. The formation of the first low-mass stars from gas with low carbon and oxygen abundances. Nature 425, 812–814 (2003).
Frebel, A., Johnson, J. L. & Bromm, V. Probing the formation of the first low-mass stars with stellar archaeology. Mon. Not. R. Astron. Soc. 380, L40–L44 (2007).
Hartwig, T. & Yoshida, N. Formation of carbon-enhanced metal-poor stars as a consequence of inhomogeneous metal mixing. Astrophys. J. Lett. 870, L3 (2019).
Skúladóttir, Á et al. Zero-metallicity hypernova uncovered by an ultra-metal-poor star in the sculptor dwarf spheroidal galaxy. Astrophys. J. Lett. 915, L30 (2021).
Skúladóttir, Á, Vanni, I., Salvadori, S. & Lucchesi, R. Tracing population III supernovae with extreme energies through the Sculptor dwarf spheroidal galaxy. Astron. Astrophys. 681, A44 (2024).
Howes, L. M. et al. Extremely metal-poor stars from the cosmic dawn in the bulge of the Milky Way. Nature 527, 484–487 (2015).
Jablonka, P. et al. The early days of the Sculptor dwarf spheroidal galaxy. Astron. Astrophys. 583, A67 (2015).
Arentsen, A. et al. The Pristine Inner Galaxy Survey (PIGS) III: carbon-enhanced metal-poor stars in the bulge. Mon. Not. R. Astron. Soc. 505, 1239–1253 (2021).
Chiti, A. et al. Enrichment by extragalactic first stars in the Large Magellanic Cloud. Nat. Astron. 8, 637–647 (2024).
Sestito, F. et al. The Pristine Inner Galaxy Survey (PIGS): X. Probing the early chemical evolution of the Sagittarius dwarf galaxy with carbon abundances. Astron. Astrophys. 690, A333 (2024).
Lucchesi, R. et al. Extremely metal-poor stars in the Fornax and Carina dwarf spheroidal galaxies. Astron. Astrophys. 686, A266 (2024).
Ryan, S. G., Aoki, W., Norris, J. E. & Beers, T. C. The origins of two classes of carbon-enhanced, metal-poor stars. Astrophys. J. 635, 349–354 (2005).
Abohalima, A. & Frebel, A. JINAbase—a database for chemical abundances of metal-poor stars. Astrophys. J. Suppl. Ser. 238, 36 (2018).
Aoki, W., Norris, J. E., Ryan, S. G., Beers, T. C. & Ando, H. Chemical composition of the carbon-rich, extremely metal poor star CS 29498-043: a new class of extremely metal poor stars with excesses of magnesium and silicon. Astrophys. J. Lett. 576, L141–L144 (2002).
Keller, S. C. et al. A single low-energy, iron-poor supernova as the source of metals in the star SMSS J031300.36-670839.3. Nature 506, 463–466 (2014).
Woosley, S. E. & Weaver, T. A. The evolution and explosion of massive stars. II. Explosive hydrodynamics and nucleosynthesis. Astrophys. J. Suppl. Ser. 101, 181 (1995).
Frebel, A. & Norris, J. E. Near-field cosmology with extremely metal-poor stars. Annu. Rev. Astron. Astrophys. 53, 631–688 (2015).
Bromm, V., Yoshida, N., Hernquist, L. & McKee, C. F. The formation of the first stars and galaxies. Nature 459, 49–54 (2009).
Naidu, R. P. et al. All the Little Things in Abell 2744: >1,000 gravitationally lensed dwarf galaxies at z = 0 − 9 from JWST NIRCam Grism spectroscopy. Preprint at https://arxiv.org/abs/2410.01874 (2024).
Nakajima, K. et al. An ultra-faint, chemically primitive galaxy forming at the epoch of reionization. Preprint at https://arxiv.org/abs/2506.11846 (2025).
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, A88 (2023).
Cameron, A. J., Katz, H., Rey, M. P. & Saxena, A. Nitrogen enhancements 440 Myr after the big bang: supersolar N/O, a tidal disruption event, or a dense stellar cluster in GN-z11?. Mon. Not. R. Astron. Soc. 523, 3516–3525 (2023).
Chiti, A. et al. An extended halo around an ancient dwarf galaxy. Nat. Astron. 5, 392–400 (2021).
Longeard, N. et al. The Pristine dwarf galaxy survey—IV. Probing the outskirts of the dwarf galaxy Boötes I. Mon. Not. R. Astron. Soc. 516, 2348–2362 (2022).
Barbosa, F. O. et al. The DECam MAGIC Survey: a wide-field photometric metallicity study of the Sculptor dwarf spheroidal galaxy. Astrophys. J. 993, 77 (2025).
Placco, V. M. et al. The DECam MAGIC Survey: Spectroscopic follow-up of the most metal-poor stars in the distant Milky Way halo. Astrophys. J. 991, 101 (2025).
Chiti, A., Frebel, A., Jerjen, H., Kim, D. & Norris, J. E. Stellar metallicities from SkyMapper Photometry I: a study of the Tucana II ultra-faint dwarf galaxy. Astrophys. J. 891, 8 (2020).
Chiti, A. et al. Stellar metallicities from SkyMapper Photometry. II. Precise photometric metallicities of ~280,000 giant stars with [Fe/H] < −0.75 in the Milky Way. Astrophys. J. Suppl. Ser. 254, 31 (2021).
Alvarez, R. & Plez, B. Near-infrared narrow-band photometry of M-giant and Mira stars: models meet observations. Astron. Astrophys. 330, 1109–1119 (1998).
Plez, B. Turbospectrum: code for spectral synthesis. Astrophysics Source Code Library record ascl:1205.004 Github https://github.com/bertrandplez/Turbospectrum2019 (2012).
Gustafsson, B. et al. A grid of MARCS model atmospheres for late-type stars. I. Methods and general properties. Astron. Astrophys. 486, 951–970 (2008).
Piskunov, N. E., Kupka, F., Ryabchikova, T. A., Weiss, W. W. & Jeffery, C. S. VALD: The Vienna Atomic Line Data Base. Astron. Astrophys. Suppl. 112, 525 (1995).
Ryabchikova, T. et al. A major upgrade of the VALD database. Physica Scripta 90, 054005 (2015).
Lindegren, L. et al. Gaia Early Data Release 3. The astrometric solution. Astron. Astrophys. 649, A2 (2021).
Dotter, A. et al. The Dartmouth Stellar Evolution Database. Astrophys. J. Suppl. Ser. 178, 89–101 (2008).
Drlica-Wagner, A. et al. An ultra-faint galaxy candidate discovered in early data from the Magellanic Satellites Survey. Astrophys. J. Lett. 833, L5 (2016).
Pace, A. B., Erkal, D. & Li, T. S. Proper motions, orbits, and tidal influences of Milky Way dwarf spheroidal galaxies. Astrophys. J. 940, 136 (2022).
Kelson, D. D. Optimal techniques in two-dimensional spectroscopy: background subtraction for the 21st century. Publ. Astron. Soc. Pac. 115, 688–699 (2003).
Freudling, W. et al. Automated data reduction workflows for astronomy. The ESO Reflex environment. Astron. Astrophys. 559, A96 (2013).
Chubak, C. et al. Precise radial velocities of 2046 nearby FGKM stars and 131 standards. Preprint at https://arxiv.org/abs/1207.6212 (2012).
Ou, X. et al. Signatures of tidal disruption of the Hercules ultrafaint dwarf galaxy. Astrophys. J. 966, 33 (2024).
Simon, J. D. et al. Nearest neighbor: the low-mass Milky Way satellite Tucana III. Astrophys. J. 838, 11 (2017).
Li, T. S. et al. Farthest neighbor: the distant Milky Way satellite Eridanus II. Astrophys. J. 838, 8 (2017).
Sneden, C. A. Carbon and Nitrogen Abundances in Metal-Poor Stars. PhD thesis, Univ. of Texas, Austin (1973).
Sobeck, J. S. et al. The abundances of neutron-capture species in the very metal-poor globular cluster M15: a uniform analysis of red giant branch and red horizontal branch stars. Astron. J. 141, 175 (2011).
Castelli, F. et al. New grids of ATLAS9 model atmospheres. In Modelling of Stellar Atmospheres—IAU Symposium (eds Piskunov N. et al.) 210, A20 (The Astronomical Society of the Pacific, 2003).
Kurucz, R. L. ATLAS12, SYNTHE, ATLAS9, WIDTH9, et cetera. Mem. Soc. Astron. Ital. Suppl. 8, 14 (2005).
Masseron, T. et al. CH in stellar atmospheres: an extensive linelist. Astron. Astrophys. 571, A47 (2014).
Sneden, C., Lucatello, S., Ram, R. S., Brooke, J. S. A. & Bernath, P. Line lists for the A2Π − X2Σ+ (red) and B2Σ+ − X2Σ+ (violet) systems of CN, 13C14N, and 12C15N, and application to astronomical spectra. Astrophys. J. Suppl. Ser. 214, 26 (2014).
Ruffoni, M. P. et al. Fe I oscillator strengths for the Gaia-ESO survey. Mon. Not. R. Astron. Soc. 441, 3127–3136 (2014).
Den Hartog, E. A. et al. Fe I oscillator strengths for transitions from high-lying even-parity levels. Astrophys. J. Suppl. Ser. 215, 23 (2014).
Belmonte, M. T. et al. Fe I oscillator strengths for transitions from high-lying odd-parity levels. Astrophys. J. 848, 125 (2017).
Pehlivan Rhodin, A., Hartman, H., Nilsson, H. & Jönsson, P. Experimental and theoretical oscillator strengths of Mg I for accurate abundance analysis. Astron. Astrophys. 598, A102 (2017).
Kramida, A., Ralchenko, Y., Reader, J. & NIST ASD Team. NIST Atomic Spectra Database (ver. 5.12). National Institute of Standards and Technology https://physics.nist.gov/asd (2024, accessed 18 May 2025).
Den Hartog, E. A. et al. Atomic transition probabilities of neutral calcium. Astrophys. J. Suppl. Ser. 255, 27 (2021).
Placco, V. M. et al. Linemake: an atomic and molecular line list generator. Res. Notes Am. Astron. Soc. 5, 92 (2021).
Casey, A. R. A Tale of Tidal Tales in the Milky Way. PhD thesis, Australian National University, Canberra (2014).
alexji/moog17scat. GitHub https://github.com/alexji/moog17scat (2026).
Atomic and molecular line list generator. GitHub http://github.com/vmplacco/linemake (2026).
Spectroscopy made harder. GitHub http://github.com/andycasey/smhr (2026).
Frebel, A., Casey, A. R., Jacobson, H. R. & Yu, Q. Deriving stellar effective temperatures of metal-poor stars with the excitation potential method. Astrophys. J. 769, 57 (2013).
Ji, A. P. et al. The southern stellar stream spectroscopic survey (S5): chemical abundances of seven stellar streams. Astron. J. 160, 181 (2020).
Placco, V. M., Frebel, A., Beers, T. C. & Stancliffe, R. J. Carbon-enhanced metal-poor star frequencies in the galaxy: corrections for the effect of evolutionary status on carbon abundances. Astrophys. J. 797, 21 (2014).
Ji, A. P. et al. Detailed abundances in the ultra-faint magellanic satellites Carina II and III. Astrophys. J. 889, 27 (2020).
JINAbase: a database for metal-poor stars. JINAbase http://jinabase.pythonanywhere.com (2026).
Ezzeddine, R., Frebel, A. & Plez, B. Ultra-metal-poor stars: spectroscopic determination of stellar atmospheric parameters using iron non-LTE line abundances. Astrophys. J. 847, 142 (2017).
Storm, N. et al. Observational constraints on the origin of the elements. IX. 3D NLTE abundances of metals in the context of Galactic Chemical Evolution models and 4MOST. Mon. Not. R. Astron. Soc. 538, 3284–3313 (2025).
Conroy, C. et al. Resolving the metallicity distribution of the Stellar Halo with the H3 Survey. Astrophys. J. 887, 237 (2019).
Youakim, K. et al. The Pristine Survey—VIII. The metallicity distribution function of the Milky Way halo down to the extremely metal-poor regime. Mon. Not. R. Astron. Soc. 492, 4986–5002 (2020).
Chiti, A., Mardini, M. K., Frebel, A. & Daniel, T. The metal-poor metallicity distribution of the ancient Milky Way. Astrophys. J. Lett. 911, L23 (2021).
Tolstoy, E. et al. A 3D view of dwarf galaxies with Gaia and VLT/FLAMES. I. The Sculptor dwarf spheroidal. Astron. Astrophys. 675, A49 (2023).
Barklem, P. S., Piskunov, N. & O’Mara, B. J. Self-broadening in Balmer line wing formation in stellar atmospheres. Astron. Astrophys. 363, 1091–1105 (2000).
Barklem, P. S. et al. Detailed analysis of Balmer lines in cool dwarf stars. Astron. Astrophys. 385, 951–967 (2002).
barklem/public-data. GitHub http://github.com/barklem/public-data (2026).
Thornton, K., Gaudlitz, M., Janka, H. T. & Steinmetz, M. Energy input and mass redistribution by supernovae in the interstellar medium. Astrophys. J. 500, 95–119 (1998).
Tominaga, N., Umeda, H. & Nomoto, K. Supernova nucleosynthesis in population III 13–50 Msolar stars and abundance patterns of extremely metal-poor stars. Astrophys. J. 660, 516–540 (2007).
Yong, D. et al. The most metal-poor stars. III. The metallicity distribution function and carbon-enhanced metal-poor fraction. Astrophys. J. 762, 27 (2013).
Roederer, I. U. et al. A search for stars of very low metal abundance. VI. Detailed abundances of 313 metal-poor stars. Astron. J. 147, 136 (2014).
Yong, D. et al. High-resolution spectroscopic follow-up of the most metal-poor candidates from SkyMapper DR1.1. Mon. Not. R. Astron. Soc. 507, 4102–4119 (2021).
Li, H. et al. Four-hundred very metal-poor stars studied with LAMOST and Subaru. II. Elemental abundances. Astrophys. J. 931, 147 (2022).
Placco, V. M. et al. Observational constraints on first-star nucleosynthesis. II. Spectroscopy of an ultra metal-poor CEMP-no Star. Astrophys. J. 833, 21 (2016).
Frebel, A. et al. Chemical abundance signature of J0023+0307: a second-generation main-sequence star with [Fe/H] <−6. Astrophys. J. 871, 146 (2019).
Hansen, T. et al. An elemental assay of very, extremely, and ultra-metal-poor stars. Astrophys. J. 807, 173 (2015).
Aguado, D. S., Allende Prieto, C., González Hernández, J. I., Rebolo, R. & Caffau, E. New ultra metal-poor stars from SDSS: follow-up GTC medium-resolution spectroscopy. Astron. Astrophys. 604, A9 (2017).
Aguado, D. S., González Hernández, J. I., Allende Prieto, C. & Rebolo, R. WHT follow-up observations of extremely metal-poor stars identified from SDSS and LAMOST. Astron. Astrophys. 605, A40 (2017).
Plez, B. & Cohen, J. G. Analysis of the carbon-rich very metal-poor dwarf G77-61. Astron. Astrophys. 434, 1117–1124 (2005).
González Hernández, J. I., Aguado, D. S., Allende Prieto, C., Burgasser, A. J. & Rebolo, R. The extreme CNO-enhanced composition of the primitive iron-poor dwarf star J0815+4729. Astrophys. J. Lett. 889, L13 (2020).
Bonifacio, P. et al. TOPoS. II. On the bimodality of carbon abundance in CEMP stars implications on the early chemical evolution of galaxies. Astron. Astrophys. 579, A28 (2015).
Caffau, E. et al. An extremely primitive star in the Galactic halo. Nature 477, 67–69 (2011).
Bonifacio, P. et al. TOPoS. IV. Chemical abundances from high-resolution observations of seven extremely metal-poor stars. Astron. Astrophys. 612, A65 (2018).
Placco, V. M. et al. Metal-poor stars observed with the Magellan Telescope. III. New extremely and ultra metal-poor stars from SDSS/SEGUE and insights on the formation of ultra metal-poor stars. Astrophys. J. 809, 136 (2015).
Frebel, A., Chiti, A., Ji, A. P., Jacobson, H. R. & Placco, V. M. SD 1313-0019: another second-generation star with [Fe/H] = −5.0, observed with the Magellan Telescope. Astrophys. J. Lett. 810, L27 (2015).
Caffau, E. et al. TOPoS. I. Survey design and analysis of the first sample. Astron. Astrophys. 560, A71 (2013).
Starkenburg, E. et al. The Pristine survey IV: approaching the Galactic metallicity floor with the discovery of an ultra-metal-poor star. Mon. Not. R. Astron. Soc. 481, 3838–3852 (2018).
Aguado, D. S. et al. Follow-up observations of extremely metal-poor stars identified from SDSS. Astron. Astrophys. 593, A10 (2016).
Mardini, M. K. et al. The chemical abundance pattern of the extremely metal-poor thin disc star 2MASS J1808-5104 and its origins. Mon. Not. R. Astron. Soc. 517, 3993–4004 (2022).
François, P. et al. Detailed abundances in a sample of very metal-poor stars. Astron. Astrophys. 642, A25 (2020).
Nordlander, T. et al. The lowest detected stellar Fe abundance: the halo star SMSS J160540.18-144323.1. Mon. Not. R. Astron. Soc. 488, L109–L113 (2019).
Lardo, C. et al. The Pristine survey—XIV. Chemical analysis of two ultra-metal-poor stars. Mon. Not. R. Astron. Soc. 508, 3068–3083 (2021).
Placco, V. M. et al. SPLUS J210428.01-004934.2: an ultra metal-poor star identified from narrowband photometry. Astrophys. J. Lett. 912, L32 (2021).
Mardini, M. K., Frebel, A. & Chiti, A. A strontium-rich ultra-metal-poor star in the Atari disc component. Mon. Not. R. Astron. Soc. 529, L60–L66 (2024).
Koch, A., McWilliam, A., Grebel, E. K., Zucker, D. B. & Belokurov, V. The highly unusual chemical composition of the Hercules Dwarf Spheroidal Galaxy. Astrophys. J. Lett. 688, L13 (2008).
Feltzing, S., Eriksson, K., Kleyna, J. & Wilkinson, M. I. Evidence of enrichment by individual SN from elemental abundance ratios in the very metal-poor dSph galaxy Boötes I. Astron. Astrophys. 508, L1–L4 (2009).
Norris, J. E. et al. Chemical enrichment in the faintest galaxies: the carbon and iron abundance spreads in the Boötes I Dwarf Spheroidal Galaxy and the Segue 1 System. Astrophys. J. 723, 1632–1650 (2010).
Norris, J. E., Yong, D., Gilmore, G. & Wyse, R. F. G. Boo-1137—an extremely metal-poor star in the ultra-faint dwarf spheroidal galaxy Boötes I. Astrophys. J. 711, 350–360 (2010).
Simon, J. D., Frebel, A., McWilliam, A., Kirby, E. N. & Thompson, I. B. High-resolution spectroscopy of extremely metal-poor stars in the least evolved galaxies: Leo IV. Astrophys. J. 716, 446–452 (2010).
Frebel, A., Simon, J. D., Geha, M. & Willman, B. High-resolution spectroscopy of extremely metal-poor stars in the least evolved galaxies: Ursa Major II and Coma Berenices. Astrophys. J. 708, 560–583 (2010).
Lai, D. K. et al. The [Fe/H], [C/Fe], and [α/Fe] distributions of the Boötes I Dwarf Spheroidal Galaxy. Astrophys. J. 738, 51 (2011).
Gilmore, G. et al. Elemental abundances and their implications for the chemical enrichment of the Boötes I Ultrafaint Galaxy. Astrophys. J. 763, 61 (2013).
Koch, A., Feltzing, S., Adén, D. & Matteucci, F. Neutron-capture element deficiency of the Hercules Dwarf Spheroidal Galaxy. Astron. Astrophys. 554, A5 (2013).
Frebel, A., Simon, J. D. & Kirby, E. N. Segue 1: an unevolved fossil galaxy from the early universe. Astrophys. J. 786, 74 (2014).
Ishigaki, M. N., Aoki, W., Arimoto, N. & Okamoto, S. Chemical compositions of six metal-poor stars in the ultra-faint dwarf spheroidal galaxy Boötes I. Astron. Astrophys. 562, A146 (2014).
Koch, A. & Rich, R. M. A chemical confirmation of the faint Boötes II dwarf spheroidal galaxy. Astrophys. J. 794, 89 (2014).
François, P. et al. Abundance ratios of red giants in low-mass ultra-faint dwarf spheroidal galaxies. Astron. Astrophys. 588, A7 (2016).
Ji, A. P., Frebel, A., Simon, J. D. & Geha, M. High-resolution spectroscopy of extremely metal-poor stars in the least-evolved galaxies: Bootes II. Astrophys. J. 817, 41 (2016).
Frebel, A., Norris, J. E., Gilmore, G. & Wyse, R. F. G. The chemical evolution of the Bootes I ultra-faint dwarf galaxy. Astrophys. J. 826, 110 (2016).
Roederer, I. U. et al. Detailed chemical abundances in the r-process-rich ultra-faint dwarf galaxy Reticulum 2. Astron. J. 151, 82 (2016).
Hansen, T. T. et al. An r-process enhanced star in the dwarf galaxy Tucana III. Astrophys. J. 838, 44 (2017).
Kirby, E. N. et al. Triangulum II. Not especially dense after all. Astrophys. J. 838, 83 (2017).
Chiti, A. et al. Chemical abundances of new member stars in the Tucana II dwarf galaxy. Astrophys. J. 857, 74 (2018).
Nagasawa, D. Q. et al. Chemical abundance analysis of three α-poor, metal-poor stars in the ultrafaint dwarf galaxy Horologium I. Astrophys. J. 852, 99 (2018).
Spite, M. et al. A CEMP-no star in the ultra-faint dwarf galaxy Pisces II. Astron. Astrophys. 617, A56 (2018).
Ji, A. P., Simon, J. D., Frebel, A., Venn, K. A. & Hansen, T. T. Chemical abundances in the ultra-faint dwarf galaxies Grus I and Triangulum II: neutron-capture elements as a defining feature of the faintest dwarfs. Astrophys. J. 870, 83 (2019).
Marshall, J. L. et al. Chemical abundance analysis of Tucana III, the second r-process enhanced ultra-faint dwarf galaxy. Astrophys. J. 882, 177 (2019).
Hansen, T. T. et al. Chemical analysis of the ultrafaint dwarf galaxy Grus II. Signature of high-mass stellar nucleosynthesis. Astrophys. J. 897, 183 (2020).
Waller, F. et al. The Cosmic Hunt for members in the outskirts of ultra-faint dwarf galaxies: Ursa Major I, Coma Berenices, and Boötes I. Mon. Not. R. Astron. Soc. 519, 1349–1365 (2023).
Webber, K. B. et al. Chemical analysis of the brightest star of the Cetus II ultrafaint dwarf galaxy candidate. Astrophys. J. 959, 141 (2023).
Hansen, T. T. et al. Chemical diversity on small scales: abundance analysis of the Tucana V ultrafaint dwarf galaxy. Astrophys. J. 968, 21 (2024).
Sestito, F. et al. The pristine inner galaxy survey (PIGS): IX. The largest detailed chemical analysis of very metal-poor stars in the Sagittarius dwarf galaxy. Astron. Astrophys. 689, A201 (2024).
Ou, X. et al. Early r-process enrichment and hierarchical assembly across the Sagittarius dwarf galaxy. Astron. J. 169, 279 (2025).
Susmitha, A., Koch, A. & Sivarani, T. Abundance analysis of a CEMP-no star in the Carina dwarf spheroidal galaxy. Astron. Astrophys. 606, A112 (2017).
Hansen, T. T. et al. Evidence for multiple nucleosynthetic processes from carbon-enhanced metal-poor stars in the Carina dwarf spheroidal galaxy. Astron. Astrophys. 674, A180 (2023).
Oh, W. S., Nordlander, T., Da Costa, G. S., Bessell, M. S. & Mackey, A. D. High-resolution spectroscopic study of extremely metal-poor stars in the Large Magellanic Cloud. Mon. Not. R. Astron. Soc. 528, 1065–1080 (2024).
Ji, A. P. et al. A nearly pristine star from the Large Magellanic Cloud. Preprint at https://arxiv.org/abs/2509.21643 (2025).
Bruce, J. et al. Spectroscopic analysis of Milky Way outer halo satellites: Aquarius II and Boötes II. Astrophys. J. 950, 167 (2023).
Cerny, W. et al. Pegasus IV: discovery and spectroscopic confirmation of an ultra-faint dwarf galaxy in the constellation Pegasus. Astrophys. J. 942, 111 (2023).
Cerny, W. et al. Discovery and spectroscopic confirmation of Aquarius III: a low-mass Milky Way satellite galaxy. Astrophys. J. 979, 164 (2025).
Chiti, A. et al. Magellan/IMACS spectroscopy of Grus I: a low metallicity ultra-faint dwarf galaxy. Astrophys. J. 939, 41 (2022).
Fritz, T. K., Carrera, R., Battaglia, G. & Taibi, S. Gaia DR 2 and VLT/FLAMES search for new satellites of the LMC. Astron. Astrophys. 623, A129 (2019).
Heiger, M. E. et al. Reading between the (Spectral) Lines: Magellan/IMACS spectroscopy of the ultrafaint dwarf galaxies Eridanus IV and Centaurus I. Astrophys. J. 961, 234 (2024).
Jenkins, S. A. et al. Very large telescope spectroscopy of ultra-faint dwarf galaxies. I. Boötes I, Leo IV, and Leo V. Astrophys. J. 920, 92 (2021).
Simon, J. D. et al. Birds of a Feather? Magellan/IMACS spectroscopy of the ultra-faint satellites Grus II, Tucana IV, and Tucana V. Astrophys. J. 892, 137 (2020).
Smith, S. E. T. et al. Discovery of a new local group dwarf galaxy candidate in UNIONS: Boötes V. Astron. J. 166, 76 (2023).
Tan, C. Y. et al. A pride of satellites in the constellation Leo? Discovery of the Leo VI Milky Way satellite ultra-faint dwarf galaxy with DELVE Early Data Release 3. Astrophys. J. 979, 176 (2025).
Pace, A. B. The Local Volume Database: a library of the observed properties of nearby dwarf galaxies and star clusters. Open J. Astrophys. 8, 142 (2025).
Yoon, J. et al. Observational constraints on first-star nucleosynthesis. I. Evidence for multiple progenitors of CEMP-no stars. Astrophys. J. 833, 20 (2016).