On the Triple Pomeron Vertex in Perturbative QCD
  We estimate the size of the triple Pomeron vertex in perturbative QCD and compare with the phenomenological value extracted from Regge fits to experimental data. For simplicity, the results of the QCD analysis are taken in the large-N_c limit. We find that the perturbative triple Pomeron coupling is of the same order of magnitude as the observed one. We also estimate the size of the Pomeron self energy and its contribution to the renormalization of the Pomeron intercept. The effect is very small, in agreement with previous nonperturbative estimates. 
J. Bartels, M.G. Ryskin, G.P. Vacca