Low mass lepton pair production in hadron collisions

Abstract

The hadroproduction of lepton pairs with mass $Q$ and transverse momentum $Q_T$ can be described in perturbative QCD by the same partonic subprocesses as prompt photon production. We demonstrate that, like prompt photon production, lepton pair production is dominated by quark-gluon scattering in the region $Q_T>Q/2$. This leads to sensitivity to the gluon density in kinematical regimes that are accessible both at collider and fixed target experiments while eliminating the theoretical and experimental uncertainties present in prompt photon production.Comment: Talk given by M. Klasen at the International Conference on the Structure and Interactions of the Photon, PHOTON 99, Freiburg i. Brsg., Germany, May 23-27, 1999. To be published in the proceedings. 6 pages, 6 postscript figure