Evidences for two scales in hadrons

Abstract

Some unusual features observed in hadronic collisions at high energies can be understood assuming that gluons in hadrons are located within small spots occupying only about 10% of the hadron's area. Such a conjecture about the presence of two scales in hadrons helps to explain: why diffractive gluon radiation so much suppressed; why the triple-Pomeron coupling shows no t-dependence; why total hadronic cross sections rise with energy so slowly; why diffraction cone shrinks so slowly, and why ${\alpha }_P^{\prime }\ll {\alpha }_R^{\prime }$; why the transition from hard to soft regimes in the structure functions occurs at rather large $Q^2$; why the observed Cronin effect at collider energies is so weak; why hard reactions sensitive to primordial parton motion (direct photon, Drell-Yan dileptons, heavy flavors, back-to-back di-hadrons, seagull effect, etc.) demand such a large transverse momenta of the projectile partons, which is not explained by NLO calculations; why the onset of nuclear shadowing for gluons is so much delayed compared to quarks, and why shadowing is so weak.

15 pages, 15 figures

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Cited by in corpus (36)

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• Higgs Hadroproduction at Large Feynman x
• Testing the Scale Dependence of the Scale Factor in Double Dijet Production at the LHC
• Hadrons and direct photon in pp and pA collisions at LHC and saturation effects
• J/Psi in high-multiplicity pp collisions: lessons from pA
• Pion structure function at small x from DIS data
• Damping of forward neutrons in pp collisions
• Measuring the saturation scale in nuclei
• The $\gamma \gamma \to J/\psi J/\psi$ reaction and the $J/\psi J/\psi$ pair production in exclusive ultraperipheral ultrarelativistic heavy ion collisions
• Heavy flavor production in high-energy $pp$ collisions: color dipole description
• Diffractive gauge bosons production beyond QCD factorisation
• Suppression vs enhancement of heavy quarkonia in pA collisions
• Study of Nuclear Suppression at Large Forward Rapidities in d-Au Collisions at Relativistic and Ultrarelativistic Energies
• Heavy quarkonium production: Nontrivial transition from pA to AA collisions
• J/Psi production in nuclear collisions: measuring the transport coefficient
• Mutual boosting of the saturation scales in colliding nuclei
• Diffraction on Nuclei: Effects of Nucleon Correlations
• Puzzles of J/Psi production off nuclei
• Two-scale hadronic structure and elastic pp scattering: predicted and measured
• BFKL Pomeron: modeling confinement
• Unitarity bound for gluon shadowing
• Applied High Energy QCD
• DPS in CGC: HBT correlations in double inclusive photon production
• DVCS via color dipoles: Nonperturbative effects
• Coherent photoproduction of heavy quarkonia on nuclei
• Diffractive Bremsstrahlung in Hadronic Collisions
• Gluonic Structure of the Constituent Quark
• DDVCS on nucleons and nuclei
• Perturbative fragmentation
• Diffractive Higgsstrahlung
• Diffractive dijet production: breakdown of factorization
• Exploring correlations in the stochastic Yang-Mills vacuum
• On the Nuclear Modification Factor at RHIC and LHC
• Dipole-pion cross section in the saturation regime
• Single-spin asymmetries in SIDIS induced by anomalous gluon-quark and photon-quark couplings
• Gluonic Distribution in the Constituent Quark and Nucleon Induced by the Instantons