The GALEX VIMOS-VLT Deep Survey Measurement of the Evolution of the 1500 Å Luminosity Function

We present the first measurement of the galaxy luminosity function (LF) at 1500 Å in the range 0.2<=z<=1.2 based on Galaxy Evolution Explorer VIMOS-VLT Deep Survey observations (~1000 spectroscopic redshifts for galaxies with NUV<=24.5) and at higher z using existing data sets. Our main results are summarized as follows: (1) Luminosity evolution is observed with ΔM_*~-2.0 mag between z=0 and z=1 and ΔM_*~-1.0 mag between z=1 and z=3. This confirms that the star formation activity was significantly higher in the past. (2) The LF slopes vary in the range -1.2>=α>=-1.65, with a marginally significant hint of increase at higher z. (3) We split the sample in three rest-frame (B-I) intervals, providing an approximate spectral type classification: Sb-Sd, Sd-Irr, and unobscured starbursts. We find that the bluest class evolves less strongly in luminosity than the two other classes. On the other hand, their number density increases sharply with z (~15% in the local universe to ~55% at z~1), while that of the reddest classes decreases.

The VIMOS-VLT Deep Survey observations have been obtained with the European Southern Observatory Very Large Telescope, Paranal, Chile.