Nature of light scalars through photon-photon collisions

Photon-photon Collisions*

Studies of photon-photon collisions are reviewed with particular emphasis on new results reported to this conference. These include results on light meson spectroscopy and deep inelastic ey scattering. Considerable work has now been accumulated on resonance production by yy collisions. Preliminary high statistics studies of the photon structure function F$(x,Q2) are given and comments are made ...

Photon - Photon Collisions

At this meeting a huge array of new and high quality experimental results for exclusive and inclusive twophoton channels has been reported, both at high and low transverse momentum and at high and low virtual photon mass.2) In many theoretical areas the precision of QCD predictions has now been sharp ened, allowing quantitative meaSures of the running coupling constant, a8(Q2), determinations o...

The Hadronic Physics of Photon-photon Collisions*

High Energy Photon-photon and Electron-photon Collisions *

The advent of a next linear e ± e − collider and back-scatterd laser beams will allow the study of a vast array of high energy processes of the Standard Model through the fusion of real and virtual photons and other gauge bosons. As examples, I discuss virtual photon scattering γ * γ * → X in the region dominated by BFKL hard Pomeron exchange and report the predicted cross sections at present a...

Higher Twist Effects in Photon-photon Collisions

In this article, we investigate the contribution of the high twist Feynman diagrams to the large-pT single pseudoscalar and vector mesons inclusive production cross section in two-photon collisions and we present the general formulae for the high and leading twist differential cross sections. The pion wave function where two non-trivial Gegenbauer coefficients a2 and a4 have been extracted from...