Creating lenticular galaxies with major mergers
  Lenticular galaxies (S0s) represent the majority of early-type galaxies in
the local Universe, but their formation channels are still poorly understood.
While galaxy mergers are obvious pathways to suppress star formation and
increase bulge sizes, the marked parallelism between spiral and lenticular
galaxies (e.g. photometric bulge-disc coupling) seemed to rule out a potential
merger origin. Here, we summarise our recent work in which we have shown,
through N-body numerical simulations, that disc-dominated lenticulars can
emerge from major mergers of spiral galaxies, in good agreement with
observational photometric scaling relations. Moreover, we show that mergers
simultaneously increase the light concentration and reduce the angular momentum
relative to their spiral progenitors. This explains the mismatch in angular
momentum and concentration between spirals and lenticulars recently revealed by
CALIFA observations, which is hard to reconcile with simple fading mechanisms
(e.g. ram-pressure stripping).
