Infrared luminosity functions from the Chandra Deep Field-South:: The Spitzer view on the history of dusty star formation at 0 ≤ z ≤ 1

We analyze a sample of similar to 2600 Spitzer MIPS 24 mu m sources brighter than similar to 80 mu Jy and located in the Chandra Deep Field - South to characterize the evolution of the comoving infrared (IR) energy density of the universe up to z similar to 1. Using published ancillary optical data, we first obtain a nearly complete redshift determination for the 24 mu m objects associated with R less than or similar to 24 mag counterparts at z less than or similar to 1. These sources represent similar to 55% - 60% of the total MIPS 24 mu m population with f(24 mu m) greater than or similar to 80 mu Jy, the rest of the sample likely lying at higher redshifts. We then determine an estimate of their total IR luminosities using various libraries of IR spectral energy distributions. We find that the 24 mu m population at 0.5 less than or similar to z less than or similar to 1 is dominated by luminous infrared galaxies'' ( i.e., 10(11) L circle dot <= LIR <= 10(12) L circle dot ), the counterparts of which appear to be also luminous at optical wavelengths and tend to be more massive than the majority of optically selected galaxies. A significant number of fainter sources ( 5 x 10(10) L circle dot less than or similar to L-IR <= 10(11) L circle dot) are also detected at similar distances. We finally derive 15 mu m and total IR luminosity functions ( LFs) up to z similar to 1. In agreement with the previous results from the Infrared Space Observatory ( ISO) and SCUBA and as expected from the MIPS source number counts, we find very strong evolution of the contribution of the IR-selected population with look-back time. Pure evolution in density is firmly excluded by the data, but we find considerable degeneracy between strict evolution in luminosity and a combination of increases in both density and luminosity [L-IR(*) proportional to (1 + z)3.2(-0.2)(+0.7) phi(IR)* proportional to (1 + z)0.7(-0.6)(+0.2)]. A significant steepening of the faint-end slope of the IR luminosity function is also unlikely, as it would overproduce the faint 24 mu m source number counts. Our results imply that the comoving IR energy density of the universe evolves as ( 1 + z)(3.9 +/- 0.4) up to z similar to 1 and that galaxies luminous in the infrared (i.e., L-IR <= 10(11) L circle dot) are responsible for 70% +/- 15% of this energy density at z similar to 1. Taking into account the contribution of the UV luminosity evolving as ( 1 + z)(similar to 2.5), we infer that these IR-luminous sources dominate the star-forming activity beyond z similar to 0: 7. The uncertainties affecting these conclusions are largely dominated by the errors in the k- corrections used to convert 24 mu m fluxes into luminosities.