Evolution of the dusty infrared luminosity function from z = 0 to z = 2.3 using observations from Spitzer

Aims. We derive the evolution of the infrared luminosity function (LF) over the last 4/5ths of cosmic time using deep 24 and 70 mu m imaging of the GOODS North and South fields. Methods. We use an extraction technique based on prior source positions at shorter wavelengths to build the 24 and 70 mu m source catalogs. The majority (93%) of the sources have a spectroscopic (39%) or a photometric redshift (54%) and, in our redshift range of interest (i.e., 1.3 < z < 2.3) similar to 20% of the sources have a spectroscopic redshift. To extend our study to lower 70 mu m luminosities we perform a stacking analysis and we characterize the observed L24/(1+z) vs. L70/(1+z) correlation. Using spectral energy distribution (SED) templates which best fit this correlation, we derive the infrared luminosity of individual sources from their 24 and 70 mu m luminosities. We then compute the infrared LF at z similar to 1.55 +/- 0.25 and z similar to 2.05 +/- 0.25. Results. We observe the break in the infrared LF up to z similar to 2.3. The redshift evolution of the infrared LF from z = 1.3 to z = 2.3 is consistent with a luminosity evolution proportional to (1 + z)(1.0 +/- 0.9) combined with a density evolution proportional to (1 + z)(-1.1 +/- 1.5). At z similar to 2, luminous infrared galaxies (LIRGs: 10(11)L(circle dot) < L-IR < 10(12) L-circle dot) are still the main contributors to the total comoving infrared luminosity density of the Universe. At z similar to 2, LIRGs and ultra-luminous infrared galaxies (ULIRGs: 10(12)L(circle dot) < LIR) account for similar to 49% and similar to 17% respectively of the total comoving infrared luminosity density of the Universe. Combined with previous results using the same strategy for galaxies at z < 1.3 and assuming a constant conversion between the infrared luminosity and star-formation rate (SFR) of a galaxy, we study the evolution of the SFR density of the Universe from z = 0 to z = 2.3. We find that the SFR density of the Universe strongly increased with redshift from z = 0 to z = 1.3, but is nearly constant at higher redshift out to z = 2.3. As part of the online material accompanying this article, we present source catalogs at 24 mu m and 70 mu m for both the GOODS-North and -South fields.