The main sequence of star forming galaxies II. A non evolving slope at
  the high mass end
  By using the deepest available mid and far infrared surveys in the CANDELS,
GOODS and COSMOS fields we study the evolution of the Main Sequence (MS) of
star forming galaxies (SFGs) from z~0 to` ~2.5 at stellar masses larger than
10^{10} M_{\odot}. The MS slope and scatter are consistent with a re-scaled
version of the local relation and distribution, shifted at higher values of SFR
according to ~(1+z)^{3.2}. The relation exhibits a bending at the high mass end
and a slightly increasing scatter as a function of the stellar mass. We show
that the previously reported evolution of the MS slope, in the considered mass
and redshift range, is due to a selection effect. The distribution of galaxies
in the MS region at fixed stellar mass is well represented by a single
log-normal distribution at all redshifts and masses, with starburst galaxies
(SBs) occupying the tail at high SFR.
