The evolution of quiescent galaxies at high redshift (z > 1.4)
Abstract
We have studied the evolution of high redshift quiescent galaxies over an effective area of ~1.7 deg^2 in the COSMOS field. Galaxies have been divided according to their star-formation activity and the evolution of the different populations has been investigated in detail. We have studied an IRAC (mag_3.6 < 22.0) selected sample of ~18000 galaxies at z > 1.4 with multi-wavelength coverage. We have derived accurate photometric redshifts (sigma=0.06) and other important physical parameters through a SED-fitting procedure. We have divided our sample into actively star-forming, intermediate and quiescent galaxies depending on their specific star formation rate. We have computed the galaxy stellar mass function of the total sample and the different populations at z=1.4-3.0. We have studied the properties of high redshift quiescent galaxies finding that they are old (1-4 Gyr), massive (log(M/M_sun)~10.65), weakly star forming stellar populations with low dust extinction (E(B-V) < 0.15) and small e-folding time scales (tau ~ 0.1-0.3 Gyr). We observe a significant evolution of the quiescent stellar mass function from 2.5 < z < 3.0 to 1.4 < z < 1.6, increasing by ~ 1 dex in this redshift interval. We find that z ~ 1.5 is an epoch of transition of the GSMF. The fraction of star-forming galaxies decreases from 60% to 20% from z ~ 2.5-3.0 to z ~ 1.4-1.6 for log(M/M_sun) > 11, while the quiescent population increases from 10% to 50% at the same redshift and mass intervals. We compare the fraction of quiescent galaxies derived with that predicted by theoretical models and find that the Kitzbichler & White (2007) model is the one that better reproduces the data. Finally, we calculate the stellar mass density of the star-forming and quiescent populations finding that there is already a significant number of quiescent galaxies at z > 2.5 (rho~6.0 MsunMpc^-3).
Keywords
Cite
@article{arxiv.1106.3194,
title = {The evolution of quiescent galaxies at high redshift (z > 1.4)},
author = {H. Domínguez Sánchez and F. Pozzi and C. Gruppioni and A. Cimatti and O. Ilbert and L. Pozzetti and H. McCracken and P. Capak and E. Le Floch and M. Salvato and G. Zamorani and C. M. Carollo and T. Contini and J. P. Kneib and O. Le Févre and S. J. Lilly and V. Mainieri and A. Renzini and M. Scodeggio and S. Bardelli and M. Bolzonella and A. Bongiorno and K. Caputi and G. Coppa and O. Cucciati and S. de la Torre and L. de Ravel and P. Franzetti and B. Garilli and A. Iovino and P. Kampczyk and C. Knobel and K. Kovac and F. Lamareille and J. F. Le Borgne and V. Le Brun and C. Maier and M. Mignoli and R. Pelló and Y. Peng and E. Pérez-Montero and E. Ricciardelli and J. D. Silverman and M. Tanaka and L. A. M. Tasca and L. Tresse and D. Vergani and E. Zucca},
journal= {arXiv preprint arXiv:1106.3194},
year = {2015}
}
Comments
17 pages, 20 figures, 5 tables. Accepted for publication in MNRAS