Zero velocity is not acting cold

I was able to get a run with 10k particles to run.  This run perturbs the initial positions of the particles by 5% of the interparticle spacing, and sets all the velocities equal to zero.  So far only two of the 6 runs have finished, but it's enough to make a density plot with (ignore the huge error bars for now).  Here it is.

What you should take away from this is that it's beginning to look like the $r^{-1/2}$ scaling is tied somehow to the fact that the particles were initially on a grid, rather than to the fact that the particles were initially cold.  Hopefully, I will have results from the runs with an initially non-uniform density profile, but at this point, I do not expect the results to differ qualitatively from these results here.