Multiplicity Structure of the Hadronic Final State in Diffractive Deep-Inelastic Scattering at HERA

Abstract

The multiplicity structure of the hadronic system X produced in deep-inelastic processes at HERA of the type ep -> eXY, where Y is a hadronic system with mass M_Y< 1.6 GeV and where the squared momentum transfer at the pY vertex, t, is limited to |t|<1 GeV^2, is studied as a function of the invariant mass M_X of the system X. Results are presented on multiplicity distributions and multiplicity moments, rapidity spectra and forward-backward correlations in the centre-of-mass system of X. The data are compared to results in e+e- annihilation, fixed-target lepton-nucleon collisions, hadro-produced diffractive final states and to non-diffractive hadron-hadron collisions. The comparison suggests a production mechanism of virtual photon dissociation which involves a mixture of partonic states and a significant gluon content. The data are well described by a model, based on a QCD-Regge analysis of the diffractive structure function, which assumes a large hard gluonic component of the colourless exchange at low Q^2. A model with soft colour interactions is also successful.

22 pages, 4 figures, submitted to Eur. Phys. J., error in first submission - omitted bibliography

Cited by in corpus (9)

• Inclusive Analysis of the b Quark Fragmentation Function in Z Decays at LEP
• Charm Cross Sections for the Tevatron Run II
• Deep inelastic scattering as a probe of entanglement: confronting experimental data
• Measurement of associated Z + charm production in proton-proton collisions at $\sqrt{s}=$ 8 TeV
• Exclusive final states in diffractive excitation
• Experimental Precision Tests for the Electroweak Standard Model
• Measurement of D mesons Production in Deep Inelastic Scattering at HERA
• Theory of Multiparticle Production in the Soft Region
• Recent Low x and Diffractive Collider Data