A measurement of direct photon production in pp collisions at a center of mass energy ∝s=63 GeV is reported. Arrays of lead-glass calorimeters and multiwire proportional chambers were used as photon detectors. Data are presented in the transverse momentum range from 4.5 to 10 GeV/c and compared with QCD predictions. The event structure of this sample is compared with that of a set dominated by high transverse momentum π O ́'s.
Bibliographical noteFunding Information:
We wish to thank the ISR Division for the excellent performance of the ISR, Robert Gros for his technical help, and Marie Anne Huber and Barbara Taylor for expert secretarial assistance. We would also like to thank P. Aurenche, R. Baier, A. Contogouris, T. Ferbel and J. Owens for stimulating and enlightening conversations. We gratefully acknowledge the Physics Department of the University of Rochester for making some computer resources available to this analysis. This research was supported in part by the National Science Foundation under grants PHY-8214679 and PHY-8607988, by the Department of Energy, and by the Science and Engineering Research Council.