Electron temperature relations and the direct N, O, Ne, S, and Ar abundances of 49 959 star-forming galaxies in DESI data release 2

Scholte, D. [Edinburgh U., Inst. Astron.] (ORCID:0000000268671244); Cullen, F. [Edinburgh U., Inst. Astron.] (ORCID:000000023736476X); Moustakas, J. M. [Siena Coll., Loudonville] (ORCID:0000000227334559); Zou, H. [Beijing Observ.] (ORCID:0000000266843997); Saintonge, A. [University Coll. London; Bonn, Max Planck Inst., Radioastron.] (ORCID:0000000343573450); Arellano-Cordova, K. Z. [Edinburgh U., Inst. Astron.] (ORCID:0000000226443518); Stanton, T. M. [Edinburgh U., Inst. Astron.] (ORCID:0000000208279769); Andrews, B. [Pittsburgh U.]; Sui, J. [Beijing Observ.]; Aguilar, J. [LBNL, Berkeley]; Ahlen, S. [Boston U.] (ORCID:0000000160987247); Bianchi, D. [Milan U.; Brera Observ.] (ORCID:0000000197120006); Brooks, D. [University Coll. London]; Castander, F. J. [Barcelona, IEEC; ICE, Bellaterra] (ORCID:0000000173164573); Cheng, T. [Groningen U.] (ORCID:0000000186704495); Claybaugh, T. [LBNL, Berkeley]; de la Macorra, A. [UNAM, Mexico] (ORCID:0000000217691640); Dey, B. [Toronto U., Astron. Dept.; Pittsburgh U.] (ORCID:0000000256657912); Doel, P. [University Coll. London]; Douglass, K. [Rochester U.] (ORCID:000000029540546X); Ferraro, S. [LBNL, Berkeley; UC, Berkeley, Math. Dept.] (ORCID:0000000349927854); Forero-Romero, J. E. [Andes U., Bogota] (ORCID:0000000228903725); Gaztañaga, E. [Barcelona, IEEC; Portsmouth U., ICG; ICE, Bellaterra] (ORCID:0000000196320815); Gontcho A. Gontcho, S. [LBNL, Berkeley; Virginia U.] (ORCID:000000033142233X); Gutierrez, G. [Fermilab]; Joyce, R. [Natl. Solar Observ., Tucson] (ORCID:0000000302015241); Kremin, A. [LBNL, Berkeley] (ORCID:0000000163567424); Lahav, O. [University Coll. London]; Landriau, M. [LBNL, Berkeley] (ORCID:0000000318388528); Le Guillou, L. [LPNHE, Paris] (ORCID:0000000171788868); Martini, P. [Chicago U., KICP; Ohio State U., Dept. Astron.; Ohio State U.] (ORCID:0000000242794182); Meisner, A. [Natl. Solar Observ., Tucson] (ORCID:0000000211257384); Miquel, R. [ICREA, Barcelona; Barcelona, IFAE]; Percival, W. J. [Waterloo U.; Perimeter Inst. Theor. Phys.] (ORCID:0000000206445727); Poppett, C. [LBNL, Berkeley; UC, Berkeley (main); UC, Berkeley, Math. Dept.]; Prada, F. [Granada U., Theor. Phys. Astrophys.] (ORCID:0000000171458674); Pérez-Ràfols, I. [Barcelona, Polytechnic U.] (ORCID:0000000169790125); Rossi, G. [Sejong U.]; Sanchez, E. [Madrid, CIEMAT] (ORCID:0000000296468198); Schlegel, D. [LBNL, Berkeley]; Shao, Z. [Shanghai Jiaotong U.]; Silber, J. [LBNL, Berkeley] (ORCID:0000000234610320); Sprayberry, D. [Natl. Solar Observ., Tucson]; Tarlé, G. [Michigan U.; KEK, Tsukuba; Hiroshima Shudo U.] (ORCID:0000000317040781); Weaver, B. A. [Natl. Solar Observ., Tucson]

doi:10.1093/mnras/stag1381

DOE OSTI · 3017447

Electron temperature relations and the direct N, O, Ne, S, and Ar abundances of 49 959 star-forming galaxies in DESI data release 2

Scholte, D. [Edinburgh U., Inst. Astron.] (ORCID:0000000268671244)·Cullen, F. [Edinburgh U., Inst. Astron.] (ORCID:000000023736476X)·Moustakas, J. M. [Siena Coll., Loudonville] (ORCID:0000000227334559)·Zou, H. [Beijing Observ.] (ORCID:0000000266843997)·Saintonge, A. [University Coll. London; Bonn, Max Planck Inst., Radioastron.] (ORCID:0000000343573450)·Arellano-Cordova, K. Z. [Edinburgh U., Inst. Astron.] (ORCID:0000000226443518)·Stanton, T. M. [Edinburgh U., Inst. Astron.] (ORCID:0000000208279769)·Andrews, B. [Pittsburgh U.]·Sui, J. [Beijing Observ.]·Aguilar, J. [LBNL, Berkeley]·Ahlen, S. [Boston U.] (ORCID:0000000160987247)·Bianchi, D. [Milan U.; Brera Observ.] (ORCID:0000000197120006)·Brooks, D. [University Coll. London]·Castander, F. J. [Barcelona, IEEC; ICE, Bellaterra] (ORCID:0000000173164573)·Cheng, T. [Groningen U.] (ORCID:0000000186704495)·Claybaugh, T. [LBNL, Berkeley]·de la Macorra, A. [UNAM, Mexico] (ORCID:0000000217691640)·Dey, B. [Toronto U., Astron. Dept.; Pittsburgh U.] (ORCID:0000000256657912)·Doel, P. [University Coll. London]·Douglass, K. [Rochester U.] (ORCID:000000029540546X)·Ferraro, S. [LBNL, Berkeley; UC, Berkeley, Math. Dept.] (ORCID:0000000349927854)·Forero-Romero, J. E. [Andes U., Bogota] (ORCID:0000000228903725)·Gaztañaga, E. [Barcelona, IEEC; Portsmouth U., ICG; ICE, Bellaterra] (ORCID:0000000196320815)·Gontcho A. Gontcho, S. [LBNL, Berkeley; Virginia U.] (ORCID:000000033142233X)·Gutierrez, G. [Fermilab]·Joyce, R. [Natl. Solar Observ., Tucson] (ORCID:0000000302015241)·Kremin, A. [LBNL, Berkeley] (ORCID:0000000163567424)·Lahav, O. [University Coll. London]·Landriau, M. [LBNL, Berkeley] (ORCID:0000000318388528)·Le Guillou, L. [LPNHE, Paris] (ORCID:0000000171788868)·Martini, P. [Chicago U., KICP; Ohio State U., Dept. Astron.; Ohio State U.] (ORCID:0000000242794182)·Meisner, A. [Natl. Solar Observ., Tucson] (ORCID:0000000211257384)·Miquel, R. [ICREA, Barcelona; Barcelona, IFAE]·Percival, W. J. [Waterloo U.; Perimeter Inst. Theor. Phys.] (ORCID:0000000206445727)·Poppett, C. [LBNL, Berkeley; UC, Berkeley (main); UC, Berkeley, Math. Dept.]·Prada, F. [Granada U., Theor. Phys. Astrophys.] (ORCID:0000000171458674)·Pérez-Ràfols, I. [Barcelona, Polytechnic U.] (ORCID:0000000169790125)·Rossi, G. [Sejong U.]·Sanchez, E. [Madrid, CIEMAT] (ORCID:0000000296468198)·Schlegel, D. [LBNL, Berkeley]·Shao, Z. [Shanghai Jiaotong U.]·Silber, J. [LBNL, Berkeley] (ORCID:0000000234610320)·Sprayberry, D. [Natl. Solar Observ., Tucson]·Tarlé, G. [Michigan U.; KEK, Tsukuba; Hiroshima Shudo U.] (ORCID:0000000317040781)·Weaver, B. A. [Natl. Solar Observ., Tucson]

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Abstract

We present the largest direct-method abundance catalogue of galaxies to date, containing measurements of 49 959 star-forming galaxies at z<0.96 from DESI (Dark Energy Spectroscopic Instrument) data release 2. By directly measuring electron temperatures across multiple ionization zones, we provide constraints on a number of electron temperature relations. Using the temperature measurements, we derive reliable abundances for N, O, Ne, S, and Ar, and measure the evolution of abundances and abundance ratios of as a function of metallicity and other galaxy properties. Our measurements include direct oxygen abundances for 49 507 galaxies, leading to the discovery of the two most metal-poor galaxies in the nearby Universe, with oxygen abundances of 12+log⁡(O/H)=6.77−0.03+0.03 dex (1.2 per cent Z⊙⁠) and 12+log⁡(O/H)=6.81−0.04+0.04 dex (1.3 per cent Z⊙⁠). We identify a rare outlier population of 24 galaxies with high-N/O ratios at low metallicity, reminiscent of galaxy abundances observed in the early Universe. We find the Ne/O ratio is constant at low metallicity but increases gradually at 12+log(O/H)>8.105±0.004 dex. We show that the S/O and Ar/O abundance ratios are strongly correlated, consistent with the expected additional Type Ia enrichment channel for S and Ar. In this work, we present an initial survey of the key properties of the sample, with this data set serving as a foundation for extensive future work on galaxy abundances at low redshift.

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BibTeX RIS

Scholte, D. [Edinburgh U., Inst. Astron.] (ORCID:0000000268671244), Cullen, F. [Edinburgh U., Inst. Astron.] (ORCID:000000023736476X), Moustakas, J. M. [Siena Coll., Loudonville] (ORCID:0000000227334559), Zou, H. [Beijing Observ.] (ORCID:0000000266843997), Saintonge, A. [University Coll. London; Bonn, Max Planck Inst., Radioastron.] (ORCID:0000000343573450), Arellano-Cordova, K. Z. [Edinburgh U., Inst. Astron.] (ORCID:0000000226443518), Stanton, T. M. [Edinburgh U., Inst. Astron.] (ORCID:0000000208279769), Andrews, B. [Pittsburgh U.], Sui, J. [Beijing Observ.], Aguilar, J. [LBNL, Berkeley], Ahlen, S. [Boston U.] (ORCID:0000000160987247), Bianchi, D. [Milan U.; Brera Observ.] (ORCID:0000000197120006), Brooks, D. [University Coll. London], Castander, F. J. [Barcelona, IEEC; ICE, Bellaterra] (ORCID:0000000173164573), Cheng, T. [Groningen U.] (ORCID:0000000186704495), Claybaugh, T. [LBNL, Berkeley], de la Macorra, A. [UNAM, Mexico] (ORCID:0000000217691640), Dey, B. [Toronto U., Astron. Dept.; Pittsburgh U.] (ORCID:0000000256657912), Doel, P. [University Coll. London], Douglass, K. [Rochester U.] (ORCID:000000029540546X), Ferraro, S. [LBNL, Berkeley; UC, Berkeley, Math. Dept.] (ORCID:0000000349927854), Forero-Romero, J. E. [Andes U., Bogota] (ORCID:0000000228903725), Gaztañaga, E. [Barcelona, IEEC; Portsmouth U., ICG; ICE, Bellaterra] (ORCID:0000000196320815), Gontcho A. Gontcho, S. [LBNL, Berkeley; Virginia U.] (ORCID:000000033142233X), Gutierrez, G. [Fermilab], Joyce, R. [Natl. Solar Observ., Tucson] (ORCID:0000000302015241), Kremin, A. [LBNL, Berkeley] (ORCID:0000000163567424), Lahav, O. [University Coll. London], Landriau, M. [LBNL, Berkeley] (ORCID:0000000318388528), Le Guillou, L. [LPNHE, Paris] (ORCID:0000000171788868), Martini, P. [Chicago U., KICP; Ohio State U., Dept. Astron.; Ohio State U.] (ORCID:0000000242794182), Meisner, A. [Natl. Solar Observ., Tucson] (ORCID:0000000211257384), Miquel, R. [ICREA, Barcelona; Barcelona, IFAE], Percival, W. J. [Waterloo U.; Perimeter Inst. Theor. Phys.] (ORCID:0000000206445727), Poppett, C. [LBNL, Berkeley; UC, Berkeley (main); UC, Berkeley, Math. Dept.], Prada, F. [Granada U., Theor. Phys. Astrophys.] (ORCID:0000000171458674), Pérez-Ràfols, I. [Barcelona, Polytechnic U.] (ORCID:0000000169790125), Rossi, G. [Sejong U.], Sanchez, E. [Madrid, CIEMAT] (ORCID:0000000296468198), Schlegel, D. [LBNL, Berkeley], Shao, Z. [Shanghai Jiaotong U.], Silber, J. [LBNL, Berkeley] (ORCID:0000000234610320), Sprayberry, D. [Natl. Solar Observ., Tucson], Tarlé, G. [Michigan U.; KEK, Tsukuba; Hiroshima Shudo U.] (ORCID:0000000317040781), Weaver, B. A. [Natl. Solar Observ., Tucson]. 2026-07-22. Electron temperature relations and the direct N, O, Ne, S, and Ar abundances of 49 959 star-forming galaxies in DESI data release 2. https://doi.org/10.1093/mnras/stag1381

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