DOI: 10.1140/epjc/s2003-01149-9
The QCD pomeron in ultraperipheral heavy ion collisions:
I. The double
production
V.P. Gonçalves1 and M.V.T. Machado2
1 Instituto de Física e Matemática, Universidade Federal de Pelotas, Caixa Postal 354, CEP 96010-090, Pelotas, RS, Brazil
2 High Energy Physics Phenomenology Group, IF-UFRGS, Caixa Postal 15051, CEP 91501-970, Porto Alegre, RS, Brazil
(Received: 12 December 2002 / Published online: 7 March 2003 )
Abstract
The contribution of the QCD pomeron to the process
is discussed. We focus on the
photon-photon collision, with the quasi-real photon coming from
the Weizsäcker-Williams spectrum of the nuclei. We calculate
the cross section for this process considering the solution of
the
LLA BFKL equation at zero momentum transfer using a small
t
approximation for the differential cross section of the
subprocess. Furthermore, the impact of non-leading corrections
to
the BFKL equation is also analyzed. In both cases the cross
section is found to increase with the energy, predicting
considerable values for the LHC energies. Moreover, we compare
our
results with the Born two-gluon approximation, which is energy
independent at the photon level. Our results indicate that the
experimental analyses of this process can be useful to
discriminate the QCD dynamics at high energies.
© Società Italiana di Fisica, Springer-Verlag 2003
