A NLO analysis on fragility of dihadron tomography in high energy $AA$ collisions

TL;DR

This paper investigates the fragility of dihadron tomography in high energy heavy-ion collisions using NLO pQCD with jet quenching, revealing the complex origins of high pT dihadron spectra and their sensitivity to initial gluon density.

Contribution

It provides a detailed NLO pQCD analysis of dihadron spectra, highlighting the different origins of high pT pairs compared to single hadrons and their dependence on initial gluon density.

Findings

High pT dihadron spectra originate from surface and center regions.

Dihadron suppression is more sensitive to initial gluon density.

Single hadron spectra are mainly from surface emission.

Abstract

The dihadron spectra in high energy $AA$ collisions are studied within the NLO pQCD parton model with jet quenching taken into account. The high $p_T$ dihadron spectra are found to be contributed not only by jet pairs close and tangential to the surface of the dense matter but also by punching-through jets survived at the center while the single hadron high $p_T$ spectra are only dominated by surface emission. Consequently, the suppression factor of such high-$p_T$ hadron pairs is found to be more sensitive to the initial gluon density than the single hadron suppression factor.