High density QCD and nucleus-nucleus scattering deeply in the saturation region

Abstract

In this paper we solve the equations that describe nucleus nucleus scattering, in high density QCD,in the framework of the BFKL Pomeron calculus. We found that (i) the contribution of short distances to the opacity for nucleus-nucleus scattering dies at high energies, (ii) the opacity tends to unity at high energy, and (iii) the main contribution that survives comes from soft (long distance) processes for large values of the impact parameter. The corrections to the opacity $Ω\Lb Y,b\Rb = 1$ were calculated and it turns out that they have a completely different form, namely($1 - Ω\to \exp\Lb - Const\,\sqrt{Y}\Rb$) than the opacity that stems from the Balisky-Kovchegov equation, which is($1 - Ω\to \exp\Lb - Const\,Y^2\Rb$). We reproduce the formula for the nucleus-nucleus cross section that is commonly used in the description of nucleus-nucleus scattering, and there is no reason why it should be correct in the Glauber-Gribov approach

25pp and 12 figures in eps format

References in corpus (54)

• Computing Quark and Gluon Distribution Functions for Very Large Nuclei
• Operator expansion for high-energy scattering
• Gluon Distribution Functions for Very Large Nuclei at Small Transverse Momentum
• 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
• Green's Functions in the Color Field of a Large Nucleus
• The BFKL Equation from the Wilson Renormalization Group
• Nonlinear Gluon Evolution in the Color Glass Condensate: II
• The Renormalization Group Equation for the Color Glass Condensate
• Unitarity at small Bjorken x
• The Wilson renormalization group for low x physics: Gluon evolution at finite parton density
• Relating different approaches to nonlinear QCD evolution at finite gluon density
• Unitarity and the BFKL Pomeron
• Factorization and high-energy effective action
• Small-x physics in perturbative QCD
• The Energy Dependence of the Saturation Momentum
• Geometric scaling as traveling waves
• Fock Space Distributions, Structure Functions, Higher Twists and Small x
• Parton Saturation at Small x and in Large Nuclei
• Solution to the evolution equation for high parton density QCD
• Parton saturation and N_part scaling of semi--hard processes in QCD
• Traveling wave fronts and the transition to saturation
• The Energy Dependence of the Saturation Momentum from RG Improved BFKL Evolution
• Quantum Corrections to the Weizsäcker--Williams Distribution Function as Small x
• Small-x physics beyond the Kovchegov equation
• Universality and tree structure of high energy QCD
• Towards a symmetric approach to high energy evolution: generating functional with Pomeron loops
• From Color Glass to Color Dipoles in high-energy onium--onium scattering
• Effective Hamiltonian for QCD evolution at high energy
• In pursuit of Pomeron loops: the JIMWLK equation and the Wess-Zumino term
• Nonlinear QCD Evolution: Saturation without Unitarization
• Rare fluctuations and the high-energy limit of the S-matrix in QCD
• Nonlinear evolution and saturation for heavy nuclei in DIS
• Nucleus-nucleus scattering in perturbative QCD with $N_c\to \infty$
• From target to projectile and back again: selfduality of high energy evolution
• No Froissart Bound from Gluon Saturation
• Perturbative Saturation and the Soft Pomeron
• Conformal invariant pomeron interaction in the perurbative QCD with large N_c
• Nucleus-nucleus interaction in the perurbative QCD
• Summing Pomeron loops in the dipole approach
• Nuclear A-dependence near the Saturation Boundary
• The spread of the gluon k_t-distribution and the determination of the saturation scale at hadron colliders in resummed NLL BFKL
• Renormalons at Low x
• Duality and Pomeron effective theory for QCD at high energy and large N_c
• QCD Reggeon Field Theory for every day: Pomeron loops included
• Solving effective field theory of interacting QCD pomerons in the semi-classical approximation
• On the Projectile-Target Duality of the Color Glass Condensate in the Dipole Picture
• A modified Balitsky-Kovchegov equation
• Conformal invariant equations for nucleus-nucleus scattering in perturbative QCD with $N_c\to \infty$
• Boundary conditions in the QCD nucleus-nucleus scattering problem
• The BFKL Pomeron Calculus in the dipole approach
• The BFKL Pomeron Calculus: Probabilistic Interpretation and High Energy Amplitude
• QCD motivated approach to soft interactions at high energies: nucleus-nucleus and hadron-nucleus collisions

Cited by in corpus (4)

• CGC/saturation approach: soft interaction at the LHC energies
• BFKL Pomeron calculus: nucleus-nucleus scattering
• The BFKL Pomeron calculus: summing enhanced diagrams
• BFKL Pomeron calculus: solution to equations for nucleus-nucleus scattering in the saturation domain