TY - JOUR
T1 - Extremely metal-poor galaxies in DESI DR1
T2 - connections to galaxies in the Early Universe
AU - Sui, Jipeng
AU - Zou, Hu
AU - Scholte, Dirk
AU - Saintonge, Amélie
AU - Mezcua, Mar
AU - Siudek, Malgorzata
AU - Li, Wenxiong
AU - Guo, Wei-Jian
AU - Liu, Shufei
AU - Xiao, Yunao
AU - Prada, Francisco
AU - Zou, Siwei
AU - Aguilar, Jessica Nicole
AU - Ahlen, Steven
AU - Prieto, Carlos Allende
AU - Bianchi, Davide
AU - Brooks, David
AU - Claybaugh, Todd
AU - Cuceu, Andrei
AU - Macorra, Axel de la
AU - Doel, Peter
AU - Forero-Romero, Jaime E.
AU - Gaztañaga, Enrique
AU - Gontcho, Satya Gontcho A
AU - Gutierrez, Gaston
AU - Hahn, ChangHoon
AU - Joyce, Dick
AU - Kehoe, Robert
AU - Landriau, Martin
AU - Guillou, Laurent Le
AU - Luo, Yifei
AU - Meisner, Aaron
AU - Miquel, Ramon
AU - Nadathur, Seshadri
AU - Palanque-Delabrouille, Nathalie
AU - Percival, Will
AU - Pérez-Ràfols, Ignasi
AU - Rossi, Graziano
AU - Sanchez, Eusebio
AU - Schlegel, David
AU - Seo, Hee-Jong
AU - Silber, Joseph Harry
AU - Sprayberry, David
AU - Tarlé, Gregory
AU - Weaver, Benjamin Alan
N1 - 17 pages, 8 figures, submitted to AJ
PY - 2026/5/18
Y1 - 2026/5/18
N2 - Extremely metal-poor galaxies (XMPGs), defined as having metallicities below 10% of the solar value, are considered possible local analogs to primordial systems and offer a unique window into early galaxy evolution. This study presents a large-scale search for XMPGs using data from the Dark Energy Spectroscopic Instrument Data Release 1, systematically evaluating their resemblance to high-redshift galaxies. From a parent sample of more than 14 million galaxies, we identify 662 (556 new) confirmed XMPGs and 763 (666 new) high-quality candidates via the direct Te method. Our results reveal that XMPGs follow a distinct star-forming main sequence (SFMS) that is elevated and shallower than that of the comparing star-forming galaxies. Notably, at higher stellar masses (M⋆ > 107.5 M⊙), the XMPG SFMS converges with the sequence observed in high-redshift galaxies by the James Webb Space Telescope, indicating that mature XMPGs sustain star formation rates comparable to their primordial counterparts. Furthermore, XMPGs consistently deviate below the local fundamental metallicity relation, mirroring high-redshift galaxy behavior. These findings demonstrate that XMPGs not only exhibit low metallicities but also preserve scaling relations characteristic of the early Universe, confirming their potential value as local laboratories for studying early galaxy formation processes.
AB - Extremely metal-poor galaxies (XMPGs), defined as having metallicities below 10% of the solar value, are considered possible local analogs to primordial systems and offer a unique window into early galaxy evolution. This study presents a large-scale search for XMPGs using data from the Dark Energy Spectroscopic Instrument Data Release 1, systematically evaluating their resemblance to high-redshift galaxies. From a parent sample of more than 14 million galaxies, we identify 662 (556 new) confirmed XMPGs and 763 (666 new) high-quality candidates via the direct Te method. Our results reveal that XMPGs follow a distinct star-forming main sequence (SFMS) that is elevated and shallower than that of the comparing star-forming galaxies. Notably, at higher stellar masses (M⋆ > 107.5 M⊙), the XMPG SFMS converges with the sequence observed in high-redshift galaxies by the James Webb Space Telescope, indicating that mature XMPGs sustain star formation rates comparable to their primordial counterparts. Furthermore, XMPGs consistently deviate below the local fundamental metallicity relation, mirroring high-redshift galaxy behavior. These findings demonstrate that XMPGs not only exhibit low metallicities but also preserve scaling relations characteristic of the early Universe, confirming their potential value as local laboratories for studying early galaxy formation processes.
KW - astro-ph.GA
U2 - 10.3847/1538-3881/ae63b5
DO - 10.3847/1538-3881/ae63b5
M3 - Article
SN - 0004-637X
VL - 171
JO - The Astrophysical Journal
JF - The Astrophysical Journal
IS - 6
M1 - 351
ER -