The HERA collider experiments H1 and ZEUS have established extensive measurement programs for diffractive vector-meson production processes during the first six years of their operation. The results provide stringent phenomenological tests of quantum chromodynamical descriptions of hard diffraction. We discuss recent topical results on Upsilon photoproduction, on decay-angle analyses of rho^0, phi and J/psi electroproduction and on rho^0 and phi photoproduction at high momentum transfer.
- Pub Date:
- November 1999
- High Energy Physics - Experiment
- Contributed to the proceedings of the Joint INT/Jefferson Lab Workshop on Exclusive and Semi-Exclusive Processes at High Momentum Transfer, 20-22 May 1999, Newport News, Virginia, USA (25 pages including 13 figures). Transparencies of the talk are available at http://www-zeus.physik.uni-bonn.de/~critten/exclu99/exclu99t/index.html