Probing quark-gluon correlation functions - art. no. 096003

We review the applicability of the QCD factorization theorem to multiple sc attering in deeply inelastic lepton-nucleus scattering. We show why an A(1/ 3)-type nuclear enhancement can be calculated consistently in perturbative QCD. We derive the transverse momentum broadening of the leading pions in d eeply 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 th e numerical values of the broadening at different values of x(B) and Q(2).