The UA8 experiment previously reported the observation of jets in diffractive events containing leading protons ("hard diffraction"), which was interpreted as evidence for the partonic structure of an exchanged Reggeon, believed to be the ℘omeron. In the present Letter, we report the final UA8 hard-diffractive (jet) cross section results and their interpretation. After corrections, the fraction of single diffractive events with mass from 118 to 189 GeV that have two scattered partons, each with Ejet T > 8 GeV, is in the range 0.002 to 0.003 (depending on xp). We determine the product, fK, of the fraction by which the ℘omeron's momentum sum rule is violated and the normalization constant of the ℘omeron-Flux-Factor of the proton. For a pure gluonic- or a pure qq̄-℘omeron, respectively: fK = (0.30 ± 0.05 ± 0.09) and (0.56 ± 0.09 ± 0.17) GeV-2.
|Number of pages||10|
|Journal||Physics Letters B|
|Publication status||Published - Mar 5 1998|
ASJC Scopus subject areas
- Nuclear and High Energy Physics