Colour connection structure of (supersymmetric) QCD ($2/to2$) processes

The colour connection structure of QCD ($2/to2$) processes is discussed, with emphasis on its application to the supersymmetric 2 parton $/to$ 2 sparton processes, which are currently being implemented in the HERWIG Monte Carlo event generator. The procedure described by Marchesini and Webber is found to be inadequate, and a new method is proposed. However, this alteration is unlikely to significantly affect the theoretical predictions for soft gluon radiation. A complete list of supersymmetric QCD $2/to2$ matrix elements and their colour decompositions is presented. (author)