Threshold Effects on Heavy Quark Production in $\gamma \gamma$ Interactions

Abstract

The exchange of gluons between heavy quarks produced in $e^{+}{e}^{-}$ interactions results in an enhancement of their production near threshold. We study QCD threshold effects in $\gamma \gamma$ collisions. The results are relevant to heavy quark production by beamstrahlung and laser back-scattering in future linear collider experiments. Detailed predictions for top, bottom and charm production are presented.

Comments: 26 pages, 12 figures available in ps upon request, revtex, MAD/PH/701 (revised version)