Off-mass-shell Sudakov-like suppression factor for the fermionic four-point function in QCD

We consider a four-point process, associated with a wide-angle elastic scat tering of two off-mass-shell spin-1/2 matter particles, in a non-abelian ga uge theory, On the basis of a worldline approach, which reverts the functio nal to a path-integral description of the system, we factorize an eikonal ( "soft") subsector of the full theory and calculate the Sudakov-like suppres sion factor for the four-point function as a whole, once we have extracted the associated anomalous dimensions and taken into account the renormalizat ion-group controlled evolution. (C) 1999 Published by Elsevier Science B.V. All rights reserved.