Regge-Eikonal Approach and its off-Shell Extention Versus Experimental Data

Abstract

We develop an off-shell extention of the Regge-eikonal approach which automatically takes into account off-shell unitarity. We argue that exclusive vector-meson production cross-sections measured at HERA can be fairly described with classical universal Regge trajectories. No extra ``hard'' trajectories of high intercept are needed for that.

Comments: 15 pages, 18 figures, uses ws-p8-50x6-00.cls, epsf.sty, amsfonts.sty, to be published in the Proceedings of the International Conference on Elastic and Diffractive Scattering (VIIIth 'Blois Workshop') June 28 - July 2, 1999 Protvino, Russia