Transverse momentum distributions in Drell-Yan processes

The gauge theory predictions are calculated in leading logarithmic approximation for the transverse momentum distribution of virtual photons produced via the Drell-Yan annihilation process. The leading contributions sum to a simple exponential form in agreement with a recent conjecture of Parisi and Petronzio and in disagreement with the finding of Dokshitser, D'Yakonov and Troyan. (Auth.)