Diffractive Phenomena at HERA

Abstract

Highlights selected from recent measurements of colour-singlet exchange processes at HERA are summarised. Particular emphasis is placed on energy and momentum transfer dependences and the decomposition of the data into an expansion in Regge trajectories. The latest results in vector meson helicity analysis, partonic descriptions of hard diffraction and diffractive dijet production are also covered.

Comments: 17 pages, 8 figures, based on talk at `Hadron Structure 98' conference, Stara Lesna, Slovakia