  This work presents the model of an ejecta cloud distribution to characterise
the plume generated by the impact of a projectile onto asteroids surfaces. A
continuum distribution based on the combination of probability density
functions is developed to describe the size, ejection speed, and ejection
angles of the fragments. The ejecta distribution is used to statistically
analyse the fate of the ejecta. By combining the ejecta distribution with a
space-filling sampling technique, we draw samples from the distribution and
assigned them a number of \emph{representative fragments} so that the evolution
in time of a single sample is representative of an ensemble of fragments. Using
this methodology, we analyse the fate of the ejecta as a function of different
modelling techniques and assumptions. We evaluate the effect of different types
of distributions, ejection speed models, coefficients, etc. The results show
that some modelling assumptions are more influential than others and, in some
cases, they influence different aspects of the ejecta evolution such as the
share of impacting and escaping fragments or the distribution of impacting
fragments on the asteroid surface.
