Quark-gluon model for diffraction at high energies

Abstract

We study elastic diffraction in the pp and pp channels at high energies through an eikonal model, built in impact-parameter space out of QCD and parton-model concepts. The eikonal function is separated into two terms, a constant contribution from valence quarks and a gluon-fusion-initiated term. The latter is responsible for the whole energy dependence of the model at high energies. We discuss the inclusion of a real part for the elastic amplitude, the removal of multiple diffraction zeros, and the behavior of our model up to the multi-TeV energy range (the Froissart bound is not saturated). We find excellent agreement with a large body of experimental data.

Exploring central opacity and asymptotic scenarios in elastic hadron scattering

“…With that in mind, we recall that the wide class of QCD inspired models, presently in the literature, had its bases in previous concepts related to semi-hard QCD or mini jet models [66][67][68][69][70][71][72][73]. The main ingredient concerned the separation of soft and semi-hard contributions in the scattering process; the former treated on phenomenological grounds and the latter determined under perturbative QCD, parton model and probabilistic arguments.…”

The Interacting Gluon Model: a review

“…Parton-parton cross sections in the nonperturbative regime have been parametrized in [77] leading to a successful quark-gluon model for elastic and diffractive scattering. Recently these non-perturbative cross sections have been calculated in the stochastic vacuum model [78].…”

“…The obtained cross sections are functions of the gluon condensate and of the gluon field correlation length, both quantities extracted from lattice QCD calculations. In order to keep our treatment simple we adopt the older parametrization for the gluon-gluon cross section used in [77]: …”

Mini-jets and multiplicity fluctuation in small rapidity intervals

“…The value of Po can not be uniquely determined , here. However, Po=2 Ge V 'is compatible with most of the calculations of the total cross section (1tot( s) of nucleon-nucleon coliisions in the framework of eikonal formalism [13][15][17) [22]. Now the multiplicity distribution for the charged particles in a rapidity interval 6yc from an inclusive hard process in the nu~leon-nucleon 2 .. ' .…”