The DESIRED strong-line calibrations: I. New empirical metallicity relations for the local and high-redshift universe
11 affiliations
- 1Instituto Nacional de Astrofísica, Óptica y Electrónica (INAOE SECIHTI) , Luis E. Erro 1, 72840, Tonantzintla, Puebla ,
- 2Instituto de Astronomía, Universidad Nacional Autónoma de México , A.P. 70-264, 04510 CDMX ,
- 3Instituto de Astrofísica de Canarias , E-38205, La Laguna, Tenerife ,
- 4Universidad de La Laguna Departamento de Astrofísica, , E-38206 La Laguna, Tenerife ,
- 5Institute for Astronomy, University of Edinburgh, Royal Observatory , Edinburgh, EH9 3HJ ,
- 6Instituto de Astronomía, Universidad Nacional Autónoma de México , A.P. 106, Ensenada 22800, BC ,
- 7Instituto de Ciencias Físicas, Universidad Nacional Autónoma de México , Av. Universidad s/n, 62210 Cuernavaca, Morelos ,
- 8Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas (CIEMAT) , Madrid ,
- 9Astronomisches Rechen-Institut, Zentrum für Astronomie der Universität Heidelberg , Mönchhofstraße 12-14, D-69120 Heidelberg ,
- 10Main Astronomical Observatory, National Academy of Sciences of Ukraine , 27 Akademika Zabolotnoho Street, UA-03680 Kyiv ,
- 11Instituto de Astrofísica de Andalucía (IAA-CSIC) , Glorieta de la Astronomía s/n, 18008 Granada ,
Abstract
We present the most comprehensive set of empirical optical strong-line metallicity calibrations to date, based on the DEep Spectra of Ionised REgions Database (DESIRED), the largest compilation of H ii regions and galaxies with direct electron-temperature determinations. We construct a high-quality calibration sample of 2392 spectra: 1029 extragalactic H ii regions, 1296 local star-forming galaxies, and 67 high-redshift (z > 2) galaxies, drawn from 201 independent literature references, spanning 12 + log (O/H) ∈ [6.79, 9.07]. Physical conditions and chemical abundances are derived homogeneously using up-to-date atomic data. We derive 27 strong-line calibrations covering oxygen-, nitrogen-, sulphur-, argon-, and neon-based line ratios, including 4 previously uncalibrated diagnostics, with reported validity ranges and intrinsic dispersions (typically ∼0.15 − 0.35 dex). For the first time in a systematic calibration framework, all relations are presented for both the homogeneous temperature case (t2 = 0) and a scenario including temperature inhomogeneities (t2 > 0), thereby reconciling abundances from recombination lines (RLs) and collisionally excited lines (CELs) and directly tackling the abundance discrepancy problem. A comparison with previous calibrations shows that the DESIRED relations span the broadest validity intervals while remaining anchored to the empirical data. Comparisons with z > 2 galaxies show that several DESIRED calibrations remain consistent with independent high-redshift relations within their intrinsic scatter, whereas others display systematic offsets associated with elevated N/O or harder ionising conditions. Thus, DESIRED calibrations can provide reliable metallicity estimates at high redshift for a subset of diagnostics, while highlighting the need to account for diagnostic-specific redshift evolution.
Related
- The JADES Mass–Metallicity and Fundamental Metallicity Relations at z ≳ 2 Using New High-redshift Metallicity Calibrations
- The AURORA Survey: High-redshift Empirical Metallicity Calibrations from Electron Temperature Measurements at z = 2–10
- Theoretical emission lines and metallicity calibrations of H II regions in ASTRID simulation
- JADES: the mass-metallicity relation at z=1−10. New calibrations, extremely metal-poor galaxies, and chemical diversity
- Empirical Effective-temperature Calibrations for Galactic BA Supergiants
BibTeX
@article{rosalesortega2026desired,
title = {{The DESIRED strong-line calibrations: I. New empirical metallicity relations for the local and high-redshift universe}},
author = {F Fabián Rosales-Ortega and J Eduardo Méndez-Delgado and Jonhatan U Guerrero-González and César Esteban and Jorge García-Rojas and Karla Z Arellano-Córdova and Alejandra Z Lugo-Aranda and Omar Espíndola-Camacho and J C López-Gutiérrez and L E Martínez-Rivero and Christophe Morisset and Maialen Orte-García and Elena Reyes-Rodríguez and L Toribio San Cipriano and Kathryn Kreckel and Oleg Egorov and Igor A Zinchenko and Sebastián F Sánchez and José M Vílchez},
journal = {Monthly Notices of the Royal Astronomical Society},
year = {2026},
month = oct,
doi = {10.1093/mnras/stag1963},
url = {https://academic.oup.com/mnras/advance-article/doi/10.1093/mnras/stag1963/8979798},
note = {CC BY 4.0},
}
RIS
TY - JOUR
TI - The DESIRED strong-line calibrations: I. New empirical metallicity relations for the local and high-redshift universe
AU - F Fabián Rosales-Ortega
AU - J Eduardo Méndez-Delgado
AU - Jonhatan U Guerrero-González
AU - César Esteban
AU - Jorge García-Rojas
AU - Karla Z Arellano-Córdova
AU - Alejandra Z Lugo-Aranda
AU - Omar Espíndola-Camacho
AU - J C López-Gutiérrez
AU - L E Martínez-Rivero
AU - Christophe Morisset
AU - Maialen Orte-García
AU - Elena Reyes-Rodríguez
AU - L Toribio San Cipriano
AU - Kathryn Kreckel
AU - Oleg Egorov
AU - Igor A Zinchenko
AU - Sebastián F Sánchez
AU - José M Vílchez
PY - 2026
DA - 2026/10/22
JO - Monthly Notices of the Royal Astronomical Society
DO - 10.1093/mnras/stag1963
UR - https://academic.oup.com/mnras/advance-article/doi/10.1093/mnras/stag1963/8979798
AB - We present the most comprehensive set of empirical optical strong-line metallicity calibrations to date, based on the DEep Spectra of Ionised REgions Database (DESIRED), the largest compilation of H ii regions and galaxies with direct electron-temperature determinations. We construct a high-quality calibration sample of 2392 spectra: 1029 extragalactic H ii regions, 1296 local star-forming galaxies, and 67 high-redshift (z > 2) galaxies, drawn from 201 independent literature references, spanning 12 + log (O/H) ∈ [6.79, 9.07]. Physical conditions and chemical abundances are derived homogeneously using up-to-date atomic data. We derive 27 strong-line calibrations covering oxygen-, nitrogen-, sulphur-, argon-, and neon-based line ratios, including 4 previously uncalibrated diagnostics, with reported validity ranges and intrinsic dispersions (typically ∼0.15 − 0.35 dex). For the first time in a systematic calibration framework, all relations are presented for both the homogeneous temperature case (t2 = 0) and a scenario including temperature inhomogeneities (t2 > 0), thereby reconciling abundances from recombination lines (RLs) and collisionally excited lines (CELs) and directly tackling the abundance discrepancy problem. A comparison with previous calibrations shows that the DESIRED relations span the broadest validity intervals while remaining anchored to the empirical data. Comparisons with z > 2 galaxies show that several DESIRED calibrations remain consistent with independent high-redshift relations within their intrinsic scatter, whereas others display systematic offsets associated with elevated N/O or harder ionising conditions. Thus, DESIRED calibrations can provide reliable metallicity estimates at high redshift for a subset of diagnostics, while highlighting the need to account for diagnostic-specific redshift evolution.
SN - 0035-8711
SN - 1365-2966
ER -