SLAC- PUB-2036 October 1977 (T/E) HADRONIC PRODUCTION WITH A DRELL-YAN TRIGGER*

We predict a dramatic change in the ratio of cross sections for producing fast ?r+@s and ~-OS in association with a massive dile#on pair as a function of the mass of the pair. For small dilepton mass the x”/r’ ratio should equal that measured in the absence of a dilepton pair. As the mass of the pair rises, the T+/~Tratio should fall by a factor of 1.7 in the reactions pi n(p+p-)X and pnn(p+p-) X, rise by a factor of 2.6 in px+ r(p+p-)X, and fall by a factor of about 25S.b pp r(p+p-)X. At FNAL and CERN SPS energies, triggering at dile@on pairs of masses m cry = 2 3 GeV should be enough to produce a clearly observable effect. Submitted to Phys. Rev. Letters *Work supper ted by The Department of Energy. **Present address: Theoretical Physics Department, Fermi National Accelerator Laboratory, P. 0. Box 500, Batavia, Illinois 60510.