The evolution of the [OII], Hβ and [OIII] emission-line luminosity functions over the last nine billions years

Emission line galaxies are one of the main tracers of the large-scale structure to be targeted by the next-generation dark energy surveys. To provide a better understanding of the properties and statistics of these galaxies, we have collected spectroscopic data from the VVDS and DEEP2 deep surveys and estimated the galaxy luminosity functions (LFs) of three distinct emission lines, [OII](λλ3726,3729)[OII](λλ3726,3729) (0.5 < z < 1.3), Hβ (λ4861) (0.3 < z < 0.8) and [OIII](λ5007)[OIII](λ5007) (0.3 < z < 0.8). Our measurements are based on 35 639 emission line galaxies and cover a volume of ∼10⁷ Mpc³. We present the first measurement of the Hβ LF at these redshifts. We have also compiled LFs from the literature that were based on independent data or covered different redshift ranges, and we fit the entire set over the whole redshift range with analytic Schechter and Saunders models, assuming a natural redshift dependence of the parameters. We find that the characteristic luminosity (L*) and density (ϕ*) of all LFs increase with redshift. Using the Schechter model over the redshift ranges considered, we find that, for [OII][OII] emitters, the characteristic luminosity L*(z = 0.5) = 3.2 × 10⁴¹ erg s−1 increases by a factor of 2.7 ± 0.2 from z = 0.5 to 1.3; for Hβ emitters L*(z = 0.3) = 1.3 × 10⁴¹ erg s⁻¹ increases by a factor of 2.0 ± 0.2 from z = 0.3 to 0.8; and for [OIII][OIII] emitters L*(z = 0.3) = 7.3 × 10⁴¹ erg s⁻¹ increases by a factor of 3.5 ± 0.4 from z = 0.3 to 0.8.