The origin of the red sequence galaxy population in the EAGLE simulation
  We investigate the evolution in colour and morphology of the progenitors of
red-sequence galaxies in the EAGLE cosmological hydrodynamical simulation. We
quantify colours with $u^{*}-r^{*}$ intrinsic magnitudes and morphologies with
a measure of the stellar kinematics. The time when galaxies moved onto the red
sequence depends on their morphology. Disc-type galaxies tend to have become
red during the last 3 Gyr, while elliptical-type galaxies joined the red
sequence earlier, with half the sample already being red 5 Gyr ago. The
time-scale, $\tau_{\rm{Green}}$, of colour transition through the `green
valley' depends weakly on the galaxy's morphological type. Elliptical-type
galaxies cross the green valley slightly faster ($\tau_{\rm{Green}}{\approx}1$
Gyr) than disc-type galaxies ($\tau_{\rm{Green}}{\approx}$1.5 Gyr). While
$\tau_{\rm{Green}}$ is similar for central and satellite galaxies, for
satellites $\tau_{\rm{Green}}$ decreases with increasing stellar mass to
host-halo mass ratio. Coupled with our finding that galaxies tend to become
green after becoming satellites, this indicates that satellite-specific
processes are important for quenching red-sequence galaxies. The last time
central, elliptical-type red-sequence galaxies left the blue cloud is strongly
correlated with the time the luminosity of the central black hole peaked, but
this is not the case for discs. This suggests that AGN feedback is important
for quenching ellipticals, particularly centrals, but not for discs. We find
only a weak connection between transformations in colour and morphology.
