---
abstract: 'We review applicability of QCD factorization theorem to multiple scattering in deeply inelastic lepton-nucleus scattering. We show why $A^{1/3}$-type nuclear enhancement can be calculated consistently in perturbative QCD. We derive the transverse momentum broadening of the leading pions in deeply inelastic lepton-nucleus collisions. We argue that the measurement of such transverse momentum broadening can provide direct information on the multiple-parton correlation functions inside a nucleus. We also estimate the numerical values of the broadening at different values of $x_B$ and $Q^2$.'
address: |
    $^1$Department of Physics and Astronomy, University of Kentucky,\
    Lexington, Kentucky 40506, USA\
    $^2$Department of Physics and Astronomy, Iowa State University\
    Ames, Iowa 50011, USA\
    $^3$Physics Department, Brookhaven National Laboratory\
    Upton, New York 11973-5000, USA 
author:
- 'Xiaofeng Guo$^1$ and Jianwei Qiu$^{2,3}$'
date: 'November 2, 1999'
title: 'Probing Quark-Gluon Correlation Functions'
---

Introduction
============

Multiparton correlation functions inside a large nucleus are extremely important and useful for understanding nuclear dependence in relativistic heavy ion collisions. When a quark or a gluon passes through the nuclear matter, it loses energy via radiation, and it picks up extra transverse momentum because of multiple scattering [@Mueller; @GW; @AHMetal; @BBL; @LQS1]. The multiple scattering is directly associated with multiparton correlation 