Effects of Perturbative Colour Interference on WW -> 6-jet Distributions

At LEP II it is hoped to measure the W mass to an accuracy of around 40 MeV. This will require direct reconstruction of the mass of the W from its decay products in both the semi-leptonic and hadronic decay channels. Final state perturbative reconnection effects in hadronic decays are considered and their effect on 6-jet distributions and the reconstructed mass. The perturbative mass shift is found to be ~ 50 keV in the negative direction.