The ALHAMBRA survey: B-band luminosity function of quiescent and star-forming galaxies at 0.2 ≤ z < 1 by PDF analysis

Publication date: 
Main author: 
López-Sanjuan C.
IAA authors: 
Benítez, N.;Molino, A.;Moles, M.;Pović, M.;Márquez, I.;Perea, J.;Alfaro, E.;Aparicio-Villegas, T.;Cerviño, M.;González Delgado, R.M.;Husillos, C.;Masegosa, J.;Del Olmo, A.;Prada, F.;Quintana, J.M.
López-Sanjuan C., Tempel E., Benítez N., Molino A., Viironen K., Díaz-García L.A., Fernández-Soto A., Santos W.A., Varela J., Cenarro A.J., Moles M., Arnalte-Mur P., Ascaso B., Montero-Dorta A.D., Pović M., Martínez V.J., Nieves-Seoane L., Stefanon M., Hurtado-Gil L., Márquez I., Perea J., Aguerri J.A.L., Alfaro E., Aparicio-Villegas T., Broadhurst T., Cabrera-Caño J., Castander F.J., Cepa J., Cerviño M., Cristóbal-Hornillos D., González Delgado R.M., Husillos C., Infante L., Masegosa J., Del Olmo A., Prada F., Quintana J.M.
Astronomy and Astrophysics
Publication type: 
Aims. Our goal is to study the evolution of the B-band luminosity function (LF) since z ∼ 1 using ALHAMBRA data. Methods. We used the photometric redshift and the I-band selection magnitude probability distribution functions (PDFs) of those ALHAMBRA galaxies with I ≤ 24 mag to compute the posterior LF. We statistically studied quiescent and star-forming galaxies using the template information encoded in the PDFs. The LF covariance matrix in redshift - magnitude - galaxy type space was computed, including the cosmic variance. That was estimated from the intrinsic dispersion of the LF measurements in the 48 ALHAMBRA sub-fields. The uncertainty due to the photometric redshift prior is also included in our analysis. Results. We modelled the LF with a redshift-dependent Schechter function affected by the same selection effects than the data. The measured ALHAMBRA LF at 0.2 ≤ z &lt; 1 and the evolving Schechter parameters both for quiescent and star-forming galaxies agree with previous results in the literature. The estimated redshift evolution of M∗ B ∝ Qz is QSF = -1.03±0.08 and QQ = -0.80±0.08, and of log10φ∗ ∝ Pz is PSF = -0.01±0.03 and PQ = -0.41 ± 0.05. The measured faint-end slopes are αSF = -1.29 ± 0.02 and αQ = -0.53 ± 0.04. We find a significant population of faint quiescent galaxies with MB ≳ -18, modelled by a second Schechter function with slope β = -1.31 ± 0.11. Conclusions. We present a robust methodology to compute LFs using multi-filter photometric data. The application to ALHAMBRA shows a factor 2.55 ± 0.14 decrease in the luminosity density jB of star-forming galaxies, and a factor 1.25 ± 0.16 increase in the jB of quiescent ones since z = 1, confirming the continuous build-up of the quiescent population with cosmic time. The contribution of the faint quiescent population to jB increases from 3% at z = 1 to 6% at z = 0. The developed methodology will be applied to future multi-filter surveys such as J-PAS. © 2017 ESO.
Galaxies: evolution; Galaxies: luminosity function, mass function; Galaxies: statistics