Eur. Phys. J. C 27, 101-113 (2003)
DOI: 10.1140/epjc/s2002-01089-x

On the triple-Pomeron vertex in perturbative QCD

J. Bartels¹, M.G. Ryskin² and G.P. Vacca<sup>3

1</sup>  II. Institut für Theoretische Physik, Universität Hamburg, Luruper Chaussee 149, 22761 Hamburg, Germany (Supported by the TMR Network "QCD and Deep Structure of Elementary Particles")
²  St. Petersburg Nuclear Physics Institute, Gatchina, St. Petersburg 188300, Russia (Work supported by the NATO Collaborated Linkage Grant SA (PST.CLG.976453)5437 and by the RFFI grant 00-15-96610)
³  Dipartimento di Fisica, Università di Bologna and Istituto Nazionale di Fisica Nucleare, Sezione di Bologna, via Irnerio 46, 40126 Bologna, Italy

(Received: 9 October 2002 / Published online: 20 December 2002)

Abstract
We estimate the size of the triple-pomeron vertex in perturbative QCD and compare with the phenomenological value extracted from Regge fits to the 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 non-perturbative estimates.

© Società Italiana di Fisica, Springer-Verlag 2003