Characterizing the ELG luminosity functions in the nearby Universe

• Autores: Favole, G.; González Perez, V.; Ascasibar, Y.; Corcho Caballero, P.; Montero Dorta, A. D.; Benson, A. J.; Comparat, J.; Cora, Sofia Alejandra; Croton, D.; Guo, H.; Izquierdo Villalba, D.; Knebe, A.; Orsi, A.; Stoppacher, D.; Vega Martínez, Cristian Antonio
• Año de publicación: 2024
• Idioma: inglés
• Tipo de recurso: artículo
• Materia: galaxies: distances and redshifts; galaxies: luminosity function, mass function; galaxies: Seyfert; galaxies: starburst; galaxies: star formation; galaxies: stellar content
• Institución: Consejo Nacional de Investigaciones Científicas y Técnicas

Context. Nebular emission lines are powerful diagnostics for the physical processes at play in galaxy formation and evolution. Moreover, emission-line galaxies (ELGs) are one of the main targets of current and forthcoming spectroscopic cosmological surveys.Aims. We investigate the contributions to the line luminosity functions (LFs) of di erent galaxy populations in the local Universe, providing a benchmark for future surveys of earlier cosmic epochs.Methods. The large statistics of the observations from the SDSS DR7 main galaxy sample and the MPA-JHU spectral catalog enabled us to precisely measure the H , H , [O II], [O III], and, for the first time, the [N II], and [S II] emission-line LFs over  2:4 Gyrs in the low-z Universe, 0.02 < z < 0.22. We present a generalized 1=Vmax LF estimator capable of simultaneously correcting for spectroscopic,r-band magnitude, and emission-line incompleteness. We studied the contribution to the LF of di erent types of ELGs classified using two methods: (i) the value of the specific star formation rate (sSFR), and (ii) the line ratios on the Baldwin–Phillips–Terlevich (BPT) and the WHAN (i.e., H  equivalent width, EWH , versus the [N ii]/H  line ratio) diagrams.Results. The ELGs in our sample are mostly star forming, with 84 percent having sSFR > 10^11 yr^-1. When classifying ELGs using the BPT+WHAN diagrams, we find that 63:3 percent are star forming, only 0.03 are passively evolving, and 1:3 have nuclear activity (Seyfert). The rest are low-ionization narrow emission-line regions (LINERs) and composite ELGs.We found that a Saunders functionis the most appropriate to describe all of the emission-line LFs, both observed and dust-extinction-corrected (i.e., intrinsic). They are dominated by star-forming regions, except for the bright end of the [O III] and [N II] LFs (i.e., L[N II] > 1042erg s^-1, L[O III] > 1043erg s^-1), where the contribution of Seyfert galaxies is not negligible. In addition to the star-forming population, composite galaxies, and LINERs are the ones that contribute the most to the ELG numbers at L < 10^41 erg s^-1. We do not observe significant evolution with redshift of our ELGs at 0.02 < z < 0.22. All of our results, including data points and analytical fits, are publicly available.Conclusions. Local ELGs are dominated by star-forming galaxies, except for the brightest [N II] and [O III] emitters, which have a large contribution of Seyfert galaxies. The local line luminosity functions are best described by Saunders functions. We expect these two conclusions to hold up at higher redshifts for the ELG targeted by current cosmological surveys, such as DESI and Euclid.
Fil: Favole, G.. Instituto de Astrofísica de Canarias; España
Fil: González Perez, V.. Universidad Autónoma de Madrid; España
Fil: Ascasibar, Y.. Universidad Autónoma de Madrid; España
Fil: Corcho Caballero, P.. Universidad Autónoma de Madrid; España
Fil: Montero Dorta, A. D.. Universidad Técnica Federico Santa María; Chile
Fil: Benson, A. J.. Carnegie Observatories; Estados Unidos
Fil: Comparat, J.. Max-planck-institut Für Extraterrestrische Physik; Alemania
Fil: Cora, Sofia Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Astrofísica La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas. Instituto de Astrofísica La Plata; Argentina
Fil: Croton, D.. Centre For Astrophysics & Supercomputing; Australia
Fil: Guo, H.. Shanghai Astronomical Observatory; China
Fil: Izquierdo Villalba, D.. Università Degli Studi Di Milano-bicocca; Italia
Fil: Knebe, A.. Universidad Autónoma de Madrid; España
Fil: Orsi, A.. Planttech Research Institute Limited; Nueva Zelanda
Fil: Stoppacher, D.. Universidad Autónoma de Madrid; España
Fil: Vega Martínez, Cristian Antonio. Universidad de La Serena; Chile. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Astrofísica La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas. Instituto de Astrofísica La Plata; Argentina