High energy factorization in nucleus-nucleus collisions II - Multigluon correlations

TL;DR

This paper extends the high-energy factorization framework to include next-to-leading order corrections for multigluon production in nucleus-nucleus collisions, emphasizing the importance of disconnected graphs and supporting the Glasma flux tube model of observed correlations.

Contribution

It provides a next-to-leading order calculation of multigluon spectra, highlighting the role of disconnected graphs and validating the factorization in a specific rapidity slice.

Findings

Disconnected graphs dominate multigluon spectra.

Factorization holds for rapidity slices with ΔY< 1/α_s.

Supports the Glasma flux tube explanation of the ridge phenomenon.

Abstract

We extend previous results (arXiv:0804.2630 [hep-ph]) on factorization in high-energy nucleus-nucleus collisions by computing the inclusive multigluon spectrum to next-to-leading order. The factorization formula is strictly valid for multigluon emission in a slice of rapidity of width \Delta Y< 1/\alpha_s. Our results show that often neglected disconnected graphs dominate the inclusive multigluon spectrum and are essential to prove factorization for this quantity. These results provide a dynamical framework for the Glasma flux tube picture of the striking "ridge"-like correlation seen in heavy ion collisions.