Nuclear dependence in direct photon production.

We calculate the nuclear dependence of direct photon production in hadronnucleus collisions. In terms of a multiple scattering picture, we factorize the cross section for direct photon production into calculable short-distance partonic parts times multiparton correlation functions in nuclei. We present the hadron-nucleus cross section as Aα times the hadron-nucleon cross section. Using information on the multiparton correlation functions extracted from photon-nucleus experiments, we compute the value of α as a function of transverse momentum of the direct photon. We also compare our results with recent data from Fermilab experiment E706. 11.80.La, 12.38Bx, 13.85.Qk, 24.80.-x Typeset using REVTEX 1