DOI: 10.1140/epjc/s2002-01089-x
On the triple-Pomeron vertex in perturbative QCD
J. Bartels1, M.G. Ryskin2 and G.P. Vacca31 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-
Nc 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