Dihadron Azimuthal Correlation from Collins Effect in Unpolarized Hadron Collisions

TL;DR

This paper predicts the azimuthal correlation of two pions produced in unpolarized proton-proton collisions at RHIC, based on the Collins effect and recent fragmentation function data, showing a sizable correlation at mid-rapidity.

Contribution

It introduces a prediction for dihadron azimuthal correlations in unpolarized collisions using the Collins fragmentation functions derived from global data analysis.

Findings

Correlation is sizable in mid-rapidity for moderate jet transverse momentum.

Uses latest Collins fragmentation functions from global analysis.

Provides predictions for RHIC energies.

Abstract

We study the dihadron azimuthal correlation produced nearly back-to-back in unpolarized hadron collisions, arising from the product of two Collins fragmentation functions. Using the latest Collins fragmentation functions extracted from the global analysis of available experimental data, we make predictions for the azimuthal correlation of two-pion production in $pp$ collisions at RHIC energies. We find that the correlation is sizable in the mid-rapidity region for moderate jet transverse momentum.