Modelling dust processing and the evolution of grain sizes in the ISM
  using the method of moments
  Interstellar dust grains do not have a single well-defined origin. Stars are
demonstrably dust producers, but also efficient destroyers of cosmic dust. Dust
destruction in the ISM is believed to be the result of SN shocks hitting the
ambient ISM gas (and dust) and lead to an increased rate of ion sputtering,
which reduces the dust mass. Grains located in cold molecular clouds can on the
other hand grow by condensation, thus providing a replenishment mechanism or
even a dominant channel of dust formation. In dense environments grains may
coagulate and form large composite grains and aggregates and if grains collide
with large enough energies they may be shattered, forming a range of smaller
debris grains. The present paper presents a statistical modelling approach
using the method of moments, which is computationally very inexpensive and may
therefore be an attractive option when combining dust processing with, e.g.,
detailed simulations of interstellar gas dynamics. A solar-neighbourhood-like
toy model of interstellar dust evolution is presented as an example.
