Single photon data in pp interactions (UA6) are in agreement with the next-to- leading order QCD calculations using a "soft" gluon structure function (Duke- Owens set I). Similar conclusions have been reached in pp, rr-p, IT+p rr+p collisions by NA24 and WA70, excluding the Duke-owens Duke-Dwens set 11 II structure structure functions. functions. The WA70 and NA24 experiments have observed a 6 standard deviation and a 2.5 standard deviation signal, respectively, for the production of rr-p~11X rr-p~llX at high Pr* PT' The measured cross-sections agree with Bll QCD predictions. The WA70 experiment measures an effective a consistent with the optimized aa of the s 5 s 5 single photon QCD perturbative theory using scale optimization. REFERENCES [1] P. Aurenche et al., Phys. lett. 1408, 140B, 87 (1984); P. Aurenche et al., Nucl. Phys. 8286, B286, 509 (1987); P. Aurenche et al., Nucl. Phys. 8297, B297, 661 (1988). [2] A. Bernasconi et al., Phys. lett. 2068, 206B, 163 (1988). [3] A.P. Contoguris, to appear in Proc. Advanced Research Workshop on QCD Hard Hadronic Processes, St. Croix Croix (Virgin (Virgin Islands), Islands), 1987. [4] D.W. Duke and J.F. Owens, Phys. Rev. D30, 49 (1984); J.F.
Owens, Phys. Rev. D30, 943 (1984). [5] C. De Marzo et al., Phys. Rev. D36, 8 (1987). [6] M. Bonesini et al., Z. Phys. C37, 535 (1988); M. Bonesini et al., Z. Phys. C38, 371 (1988).