High energy behaviour of gamma gamma to f f(bar) processes in SM and MSSM

Abstract

We compute the leading logarithms electroweak contributions to gamma gamma to f f(bar) processes in SM and MSSM. Several interesting properties are pointed out, such as the importance of the angular dependent terms, of the Yukawa terms, and especially of the $\tan^2\beta$ dependence in the SUSY contributions. These properties are complementary to those found in e+e- to f f(bar). These radiative correction effects should be largely observable at future high energy gamma gamma colliders. Polarized beams would bring interesting checks of the structure of the one loop corrections. We finally discuss the need for two-loop calculations and resummation.