Interactions of virtual photons are analyzed in terms of photon structure. It is argued that the concept of parton distribution functions is phenomenologically very useful even for highly virtual photons involved in hard collisions. The role of longitudinal photons for proper interpretation of jet cross--sections in the region of moderate virtualities accessible at HERA is investigated.
- Pub Date:
- May 1999
- High Energy Physics - Phenomenology
- 15 pages, Latex, 10 encapsulated eps figures. Three references updated, a few misprints corrected and several paragraphs slightly reworded. Contribution to the Workshop MC generators for HERA Physics