Photon - Photon Collisions at the Next Linear Collider : Theory

The collisions of photons at a high energy electron-positron collider provide a comprehensive laboratory for testing QCD, electroweak interactions, and extensions of the standard model. It is expected that by using back-scattered laser beams, that the effective luminosity and, energy of photon-photon collisions will be comparable to that of the primary c+e-collisions. In this talk, I will focus on tests of electroweak theory in photon-photon annihilation such as yy t W+W-, yy + Higgs bosons, and higher-order loop processes, such as yy + yy, Zy and 22. Since each photon can be resolved into a W+W-pair, high energy photon-photon collisions can also provide a remarkably background-free laboratory for studying WW collisions and annihilation. I also review high energy yy tests of quantum chro-modynamics, such as the scaling of the photon structure function, t? production, mini-jet processes, and diffractive reactions. ABSTRACT. The collisions of photons at a high energy electron-positron collider provide a comprehensive laboratory for testing QCD, electroweak interactions, and extensions of the standard model. It is expected that by using back-scattered 1-r beams, that the effective luminosity and energy of photon-photon collisions will be comparable to that of the primary e+e' collisions. In this talk, I will focus on tests of electroweak theory in photon-photon annihilation such as yy-W+W-, yy-Higgs bosons, and higher-order loop processes, such as yy-yy, Zy and ZZ. Since each photon can be resolved into a Wt W-pair, high energy photon-photon collisions can also provide a remarkably background-free laboratory for studying WW collisions and annihilation. I also review high energy yy tests of quantum chromodynamics, such as the scaling of the photon structure function, tj production, mini-jet processes, and diffractive reactions.