Dust evolution processes constrained by extinction curves in nearby
  galaxies
  Extinction curves, especially those in the Milky Way (MW), the Large
Magellanic Cloud (LMC), and the Small Magellanic Cloud (SMC), have provided us
with a clue to the dust properties in the nearby Universe. We examine whether
or not these extinction curves can be explained by well known dust evolution
processes. We treat the dust production in stellar ejecta, destruction in
supernova shocks, dust growth by accretion and coagulation, and dust disruption
by shattering. To make a survey of the large parameter space possible, we
simplify the treatment of the grain size distribution evolution by adopting the
`two-size approximation', in which we divide the grain population into small
($\lesssim 0.03~\mu$m) and large ($\gtrsim 0.03~\mu$m) grains. It is confirmed
that the MW extinction curve can be reproduced in reasonable ranges for the
time-scale of the above processes with a silicate-graphite mixture. This
indicates that the MW extinction curve is a natural consequence of the dust
evolution through the above processes. We also find that the same models fail
to reproduce the SMC/LMC extinction curves. Nevertheless, this failure can be
remedied by giving higher supernova destruction rates for small carbonaceous
dust and considering amorphous carbon for carbonaceous dust; these modification
fall in fact in line with previous studies. Therefore, we conclude that the
current dust evolution scenario composed of the aforementioned processes is
successful in explaining the extinction curves. All the extinction curves favor
efficient interstellar processing of dust, especially, strong grain growth by
accretion and coagulation.
