Scattering of color dipoles: from low to high energies
  A dipole-dipole scattering amplitude is calculated exactly in the first two orders of perturbation theory. This amplitude is an analytic function of the relative energy and the dipoles' sizes. The cross section of the dipole-dipole scattering approaches the high-energy BFKL asymptotics starting from a relatively large rapidity $\sim 5$. 
Alexander Babansky and Ian Balitsky (JLab/Old Dominion Univ.)