Dihadron Azimuthal Correlations in Deep-Inelastic Scattering Off Nuclear Targets

TL;DR

This study investigates how nuclear size affects di-pion azimuthal correlations in deep-inelastic scattering, revealing broadening effects and kinematic dependencies, and highlights the limitations of current Monte Carlo models.

Contribution

First measurement of nuclear dependence of di-pion azimuthal correlations in DIS, providing new insights into nuclear effects on hadronization.

Findings

Correlation function broadens with larger nuclei

Shape depends on pion transverse momentum and rapidity difference

Monte Carlo models do not fully reproduce observed effects

Abstract

We measured the nuclear dependence of the di-pion azimuthal correlation function in deep-inelastic scattering (DIS) using the CEBAF Large Acceptance Spectrometer (CLAS) and a 5 GeV electron beam. As the nuclear-target size increases, transitioning from deuterium to carbon, iron, and lead, the correlation function broadens monotonically. Its shape exhibits a significant dependence on kinematics, including the transverse momentum of the pions and the difference in their rapidity. None of the various Monte-Carlo event generators we evaluated could fully replicate the observed correlation functions and nuclear effects throughout the entire phase space. As the first study of its kind in DIS experiments, this research provides an important baseline for enhancing our understanding of the interplay between the nuclear medium and the hadronization process in these reactions.