An analysis of diffraction in deep-inelastic scattering

Abstract

We propose a simple parametrization for the deep-inelastic diffractive cross section. It contains the contribution of qq production to both the longitudinal and the transverse diffractive structure functions, and of the production of qqg final states from transverse photons. We start from the hard region and perform a suitable extrapolation into the soft region. We test our model on the 1994 ZEUS and H1 data, and confront it with the H1 conjecture of a singular gluon distribution.

Diffractive parton distributions from the analysis with higher twist

“…However, by analyzing diffractive final states in the dipole approach it was found that for diffractive mass M 2 Q 2 ( ! 1), the twist-4 contribution dominates over the vanishing twist-2 one [19,40,41]. This observation is made on the basis of the perturbative QCD calculations in which the diffractive state is formed by the q q and q qg systems interacting with a proton through a colorless gluonic exchange which is a model of the pomeron interactions in QCD.…”

High momentum diffractive processes and hadronic structure

“…Q 2 is the photon virtuality. Similar expressions are given in [107,108]. The predicted LCWFs for the electromagnetic component are based on quantum electrodynamics and can be considered precise.…”

Target-mass and finite t corrections to diffractive deep-inelastic scattering

“…The non-perturbative effects cannot be calculated by rigorous methods within Quantum Chromodynamics at present, but are left to phenomenological models or are determined through fits to data, cf. [14][15][16][17][18][19][20][21][22][23].…”

“…The process of deep-inelastic diffractive scattering was first described phenomenologically [14][15][16][17][18][19][20][21][22][23]. A consistent field-theoretic description of the process requires factorization for the twist-2 contributions [24][25][26].…”