Bibcode
Orte-García, M.; Esteban, C.; Méndez-Delgado, J. E.; García-Rojas, J.; Arellano-Córdova, K. Z.; Rosales-Ortega, F. F.; Reyes-Rodríguez, E.
Bibliographical reference
Astronomy and Astrophysics
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5
2025
Journal
Citations
0
Refereed citations
0
Description
Aims. We aim to study the behaviour of Cl abundance and its ratios with respect to O, S, and Ar abundances in a sample of more than 200 spectra of Galactic and extragalactic H II regions and star-forming galaxies (SFGs) of the local Universe. Methods. We used the DEep Spectra of Ionised REgions Database (DESIRED) Extended project (DESIRED-E) that comprises more than 2000 spectra of H II regions and SFGs with direct determinations of electron temperature (Te). From this database, we selected spectra for which it is possible to determine the Cl2+ abundance and whose line ratios meet certain observational criteria. We calculated the physical conditions and Cl, O, S, and Ar abundances in a homogeneous manner for all the spectra. We compared them with results of photoionisation models to carry out an analysis of which is the most appropriate Te indicator for the nebular volume where Cl2+ lies, proposing a scheme that improves the determination of the Cl2+ abundance. We compared the Cl/O ratios obtained using two different ionisation correction factor (ICF) schemes. We also compared the nebular Cl/O distribution with stellar determinations. Results. Our analysis indicates that one of the tested ICF schemes provides a better match to the observed Cl/O ratio distributions. We find that the log(Cl/O) versus 12+log(O/H) and log(Cl/Ar) versus 12+log(Ar/H) distributions are not correlated in the whole metallicity range covered by our objects indicating a lockstep evolution of those elements. In contrast, the log(Cl/S) versus 12+log(S/H) distribution shows a weak correlation with a slight negative slope.