Quantitative study of the transverse correlation of soft gluons in high energy QCD

Abstract

We examine both analytically and numerically the validity of factorization for the double dipole scattering amplitude T^{(2)} which appears on the right hand side of the BK--JIMWLK equation. We demonstrate that, if one uses a dilute object (e.g., a proton in DIS) as the initial condition, the correlation in the transverse plane induced by the leading order BFKL evolution is generally strong, resulting in a violation of the mean field approximation T^{(2)} \approx TT even at zero impact parameter by a factor ranging from 1.5 to O(10) depending on the relative size of the scatterers and rapidity. This suggests that, within the experimentally accessible energy interval, the transverse correlation can significantly affect the nonlinear evolution of the dipole scattering amplitude. It also suggests that the nonlinear effects may set in earlier, already in the weak scattering regime. In the case of the simulation with a running coupling, the violation of factorization is somewhat milder, but still noticeable.

References in corpus (23)

• Operator expansion for high-energy scattering
• Small-x F_2 Structure Function of a Nucleus Including Multiple Pomeron Exchanges
• Nonlinear Gluon Evolution in the Color Glass Condensate: I
• The Wilson renormalization group for low x physics: towards the high density regime
• The Wilson renormalization group for low x physics: Gluon evolution at finite parton density
• NLO evolution of color dipoles
• Saturation Physics and Deuteron--Gold Collisions at RHIC
• Evolution at small x_bj: The Color Glass Condensate
• Quark contribution to the small-$x$ evolution of color dipole
• Triumvirate of Running Couplings in Small-x Evolution
• Universal features of JIMWLK and BK evolution at small x
• A Linear Evolution for Non-Linear Dynamics and Correlations in Realistic Nuclei
• Conformal bootstrap for the BFKL Pomeron
• Small-x Dipole Evolution Beyond the Large-N_c Limit
• Pomeron loop and running coupling effects in high energy QCD evolution
• Dual Shapiro-Virasoro amplitudes in the QCD dipole picture
• Correlation of small-x gluons in impact parameter space
• Diffractive Excitation in DIS and pp Collisions
• The double parton distributions in the hard pomeron model
• QCD Saturation Equations including Dipole-Dipole Correlation
• INITIAL-STATE COLOUR DIPOLE EMISSION ASSOCIATED WITH QCD POMERON EXCHANGE
• On the anomalous dimensions of the multiple pomeron exchanges
• BFKL ansatz for BK equation in conformal basis

Cited by in corpus (14)

• Resummation of non-global logarithms at finite $N_c$
• Subleading-N_c corrections in non-linear small-x evolution
• Angular and long range rapidity correlations in particle production at high energy
• Eccentricity and elliptic flow in proton-proton collisions from parton evolution
• On Angular Correlations and High Energy Evolution
• Constraint fitting of experimental data with a jet quenching model embedded in a hydrodynamical bulk medium
• Non-global logarithms in hadron collisions at $N_c=3$
• Soft gluons away from jets: distribution and correlation
• Elliptic Flow in Small Systems due to Elliptic Gluon Distributions?
• Froissart bound and gluon number fluctuations
• Jets in 200 GeV p+p and d+Au collisions from the STAR experiment at RHIC
• Cold nuclear effects on heavy flavours (a review)
• Heavy-Flavor Measurements by the PHENIX Experiment at RHIC
• Multiparticle Dynamics in the LHC Era