[O II] emitters in MultiDark-Galaxies and DEEP2

FAVOLE, G.; GONZALEZ-PEREZ, V.; STOPPACHER, D.; ORSI, A.; COMPARAT, J.; CORA, S.A.; VEGA-MARTÍNEZ, C.A.; STEVENS, A.R.H.; MARASTON, C.; CROTON, D.; KNEBE, A.; BENSON, A.J.; MONTERO-DORTA, A.D.; PADILLA, N.; PRADA, F.; THOMAS, D.

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY

WILEY-BLACKWELL PUBLISHING, INC

Año: 2020 vol. 497 p. 5432 - 5453

0035-8711

We use three semi-analytical models (SAMs) of galaxy formation and evolution run on the same 1 h-1 Gpc MultiDark Planck2 cosmological simulation to investigate the properties of [O ii] emission line galaxies at redshift z 1. We compare model predictions with different observational data sets, including DEEP2-firefly galaxies with absolute magnitudes. We estimate the [O ii] luminosity (L{≤ft[m{O,{small II}}ight]) of our model galaxies using the public code get emlines, which ideally assumes as input the instantaneous star formation rates (SFRs). This property is only available in one of the SAMs under consideration, while the others provide average SFRs, as most models do. We study the feasibility of inferring galaxies´ L{≤ft[m{O,{small II}}ight] from average SFRs in post-processing. We find that the result is accurate for model galaxies with dust attenuated L{≤ft[m{O,{small II}}ight] ≳ 1042.2 erg s-1 (lt 5{{ m per cent} discrepancy). The galaxy properties that correlate the most with the model L{≤ft[m{O,{small II}}ight] are the SFR and the observed-frame u and g broad-band magnitudes. Such correlations have r-values above 0.64 and a dispersion that varies with L{≤ft[m{O,{small II}}ight]. We fit these correlations with simple linear relations and use them as proxies for L{≤ft[m{O,{small II}}ight], together with an observational conversion that depends on SFR and metallicity. These proxies result in [O ii] luminosity functions and halo occupation distributions with shapes that vary depending on both the model and the method used to derive L{≤ft[m{O,{small II}}ight]. The amplitude of the clustering of model galaxies with L{≤ft[m{O,{small II}}ight] >1040.4 erg s-1 remains overall unchanged on scales above 1 , h^{-1 Mpc, independently of the L{≤ft[m{O,{small II}}ight] computation.