The stellar mass assembly of galaxies from z=0 to z=4. Analysis of a sample selected in the rest-frame near-infrared with Spitzer

Understand

Using a sample of ~28,000 sources selected at 3.6-4.5 microns with Spitzer observations of the HDF-N, the CDF-S, and the Lockman Hole (surveyed area: ~664 arcmin^2), we study the evolution of the stellar mass content of the Universe at 0<z<4.

• We calculate stellar masses and photometric redshifts, based on ~2,000 templates built with stellar and dust emission models fitting the UV-to-MIR SEDs of galaxies with spectroscopic redshifts.
• We estimate stellar mass functions for different redshift intervals.
• We find that 50% of the local stellar mass density was assembled at 0<z<1 (average SFR:0.048 M_sun/yr/Mpc^3), and at least another 40% at 1<z<4 (average SFR: 0.074 M_sun/yr/Mpc^3).