  The outcome of collisions between small icy bodies, such as Kuiper belt
objects, is poorly understood and yet a critical component of the evolution of
the trans-Neptunian region. The expected physical properties of outer solar
system materials (high porosity, mixed ice-rock composition, and low material
strength) pose significant computational challenges. We present results from
catastrophic small body collisions using a new hybrid hydrocode to $N$-body
code computational technique. This method allows detailed modeling of shock
propagation and material modification as well as gravitational reaccumulation.
Here, we consider a wide range of material strengths to span the possible range
of Kuiper belt objects. We find that the shear strength of the target is
important in determining the collision outcome for 2 to 50-km radius bodies,
which are traditionally thought to be in a pure gravity regime. The
catastrophic disruption and dispersal criteria, $Q_D^*$, can vary by up to a
factor of three between strong crystalline and weak aggregate materials. The
material within the largest reaccumulated remnants experiences a wide range of
shock pressures. The dispersal and reaccumulation process results in the
material on the surfaces of the largest remnants having experienced a wider
range of shock pressures compared to material in the interior. Hence, depending
on the initial structure and composition, the surface materials on large,
reaccumulated bodies in the outer solar system may exhibit complex spectral and
albedo variations. Finally, we present revised catastrophic disruption criteria
for a range of impact velocities and material strengths for outer solar system
bodies.
