  Let $\Omega$ be a bounded domain in $\R^n$ whose boundary is
$\ka{1,\,\gamma}$ for $\gamma\in(0,\,1)$. Consider the aggregation equation in
the case of the initial condition being a positive multiple of the
characteristic function of $\Omega$. In this paper we prove global in time
analyticity of the flow generated by the velocity field which propagates the
density solution of this equation.
