Renormalization group evolution of multi-gluon correlators in high energy QCD

TL;DR

This paper numerically solves the Balitsky-JIMWLK hierarchy to evaluate multi-gluon correlators in high energy QCD, providing insights into their evolution and implications for multi-gluon final states in particle collisions.

Contribution

It introduces a numerical solution to the Balitsky-JIMWLK hierarchy for multi-gluon correlators, improving upon previous mean-field and large N_c approximations.

Findings

Numerical evaluation of multi-gluon correlators using Langevin equations.

Comparison of results with Gaussian and large N_c approximations.

Implications for understanding multi-gluon states in high energy collisions.

Abstract

Many-body QCD in leading high energy Regge asymptotics is described by the Balitsky-JIMWLK hierarchy of renormalization group equations for the x evolution of multi-point Wilson line correlators. These correlators are universal and ubiquitous in final states in deeply inelastic scattering and hadronic collisions. For instance, recently measured di-hadron correlations at forward rapidity in deuteron-gold collisions at the Relativistic Heavy Ion Collider (RHIC) are sensitive to four and six point correlators of Wilson lines in the small x color fields of the dense nuclear target. We evaluate these correlators numerically by solving the functional Langevin equation that describes the Balitsky-JIMWLK hierarchy. We compare the results to mean-field Gaussian and large N_c approximations used in previous phenomenological studies. We comment on the implications of our results for quantitative studies of multi-gluon final states in high energy QCD.