Multiple Gluon Effects in Fermion--(Anti)Fermion Scattering at SSC/LHC Energies

Abstract

We extend the methods of Yennie, Frautschi and Suura (YFS) to compute, via Monte Carlo methods, the effects of multiple gluon emission in the processes $q+q'\to q''+q'''+n(G)$, where $G$ is a soft gluon. We show explicitly that the infrared singularities in the respective simulations are canceled to all orders in $\alpha_s$. Some discussion of this result from the standpoint of confinement is given. More importantly, we present, for the first time ever, sample numerical Monte Carlo data on multiple soft gluon emission in the rigorously extended YFS framework. We find that such soft gluon effects must be taken into account for precise SSC/LHC physics simulations.