BFKL signatures at a linear collider

Abstract

The BFKL dynamics can be successfully tested at the future high energy $e^{+}{e}^{-}$ linear collider. The total ${\gamma }^{\ast }{\gamma }^{\ast }$ cross-section is calculated in the Leading Log QCD dipole picture of BFKL dynamics, and compared with the one from 2-gluon exchange. The rapidity dependence of the cross-section remains a powerful tool to increase the ratio between the BFKL and the 2-gluon cross-sections and is more sensitive to BFKL effects, even in the presence of higher order corrections. Other potential signals like diffractive $J/\Psi$ and 'forward' jet productions will also be discussed.

Invited talk given at the International Workshop on Linear Colliders (LCWS99), April 28- May 5, Sitges (Spain)