Mapping the proton unintegrated gluon distribution in dijets correlations in real and virtual photoproduction at HERA

Abstract

We discuss how the dijet azimuthal correlations in DIS and real photoproduction at HERA probe the differential (unintegrated) gluon distribution in the proton. We find a strong dependence of the azimuthal correlation pattern on Bjorken-$x$, photon virtuality and the cut on the jet transverse momenta. A rise of the azimuthal decorrelations is observed with decreasing Bjorken-x due to the interplay of perturbative and nonperturbative effects. We predict a strong rise of the same-side jet rate with photon energy for real photoproduction. We discuss conditions for the correlation function to be dominated by hard perturbative gluons and ways of constraining the size of the nonperturbative soft component. We make some predictions for the THERA energy range. The analysis of the energy dependence of the isolated jet and two-jet cross sections in photoproduction would be a new way to study the not yet well constrained unintegrated gluon distributions and to explore the onset of the pQCD regime.

16 pp, 8 eps-figs

References in corpus (4)

• Predicting F2D(3) from the dipole cross-section
• Measurement of Di-jet Cross-Sections in Photoproduction and Photon Structure
• Measurement of Dijet Photoproduction at High Transverse Energies at HERA
• Predictions for dijet production in DIS using small x dynamics

Cited by in corpus (16)

• A Large Hadron Electron Collider at CERN: Report on the Physics and Design Concepts for Machine and Detector
• Small x Phenomenology - summary of the 3rd Lund Small x Workshop in 2004
• kt - factorization and CCFM - the solution for describing the hadronic final states - everywhere ?
• Inclusive Dijet Production at Low Bjorken-x in Deep Inelastic Scattering
• Nonlinear kT factorization for Forward Dijets in DIS off Nuclei in the Saturation Regime
• Central ${\mu }^{+}{\mu }^{-}$ production via photon-photon fusion in proton-proton collisions with proton dissociation
• Nonuniversality Aspects of Nonlinear k_\perp-factorization for Hard Dijets
• Decomposition of the QCD String into Dipoles and Unintegrated Gluon Distributions
• Charm quark-antiquark correlations in photon-proton scattering
• Unintegrated gluon distributions and Higgs boson production in proton-proton collisions
• Dijet correlations at RHIC, leading-order $k_t$-factorization approach versus next-to-leading order collinear approach
• Why Breakup of Photons and Pions into Forward Dijets Is so Different: Predictions from Nonlinear Nuclear k_t-factorization
• Dilepton production through timelike Compton scattering within the $k_T$-factorization approach
• High Density QCD, Saturation and Diffractive DIS
• Forward pion production at large transverse momenta in pp collisions and beyond
• Dijet and photon-jet correlations in proton-proton collisions at RHIC